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Graphing Linear Equations Chapter Questions 1. What are the various types of information you can be given to graph a line? 2. What is slope? How is it determined? 3. Why do we need to be careful about the slopes of horizontal and vertical lines? 4. How can we tell is two lines are parallel, perpendicular or neither just from their equations? 5. What are the various ways you can use information given to you to determine the equation of a line? 6. What are the different ways to solve a system of linear equations? 7. When do you get an answer to a system of linear equations that has one solution, no solution and infinitely many solutions? NJ Center for Teaching and Learning ~ 1 ~ www.njctl.org

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Graphing Linear Equations Chapter Questions

1. What are the various types of information you can be given to graph a line?

2. What is slope? How is it determined?

3. Why do we need to be careful about the slopes of horizontal and vertical lines?

4. How can we tell is two lines are parallel, perpendicular or neither just from their equations?

5. What are the various ways you can use information given to you to determine the equation of a line?

6. What are the different ways to solve a system of linear equations?

7. When do you get an answer to a system of linear equations that has one solution, no solution and infinitely many solutions?

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Graphing Linear Equations Chapter Problems

Tables

Classwork

For the equations below, make a table with at least 3 ordered pairs, plot the points and connect them to form the line.

1) y = 3x - 4

2) y = -2x + 4

3) y = x – 3

4) y = x + 4

5) y = - x + 1

Homework

For the equations below, make a table with at least 3 ordered pairs, plot the points and connect them to form the line.

6) y = -x – 2

7) y = 2x + 1

8) y = x

9) y = -2x – 2

10) y = - x + 4

Slope and y-intercept

Classwork

11) Use lines A, B, C and D to fill in the table.

Lines y intercept Slope (+, -, 0 or undefined

A

B

C

D

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12) What is the slope of lines E, F, G and H?

13) What are the equations of lines E, F ,G and H?

Lines Equation

E

F

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Lines slope

E

F

G

H

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G

H

Homework

14) Use lines I, J, K and L to fill in the table.

Lines y intercept Slope (+, -, 0 or undefined

I

J

K

L

15) What are the slopes of lines M, N, O and P?

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Lines slope

M

N

O

P

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16) What is the equation of lines M, N, O and P?

Lines Equation

M

N

O

P

Slope Formula

Classwork Find the slope of the line through each of the following two points.

17) (-12,-5), (0,-8)

18) (12,-18),(11,12)

19) (-18,-20),(-18,-15)

20) (-20,-4),(-12,-10)

21) (8,10),(0,14)

22) (6,9),(3,-9)

23) (1,2),(5,7)

24) (3,-3),(12,-2)

25) (-4,-8),(-1,1)

26) (4,7),(-3,7)

Homework Find the slope of the line through each of the following two points.

27) (3,-9),(1,1)

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28) (7,4),(3,8)

29) (-3,0),(5,12)

30) (8,-2),(12,-2)

31) (6,-3),(2,9)

32) (-3,7),(-4,8)

33) (5,9),(5,-8)

34) (-5, 0.5),(-6,3)

35) (-7,1),(7,8)

36) (-2,1),(5,7)

Slope Intercept Form

37) Write the equation for each graph that is for the line.

Which graph represents the following equations?

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38) y = - 4

39) y = -x + 5

40) y = -3/8x – 6

41) y = 3/2x

Homework

42) Write the equation that represents the following graphs.

Which graph represents the following equations?

43) y = -4/5 -8

44) y = 8

45) y = 5/4x -1

46) y = -3x + 2

Rate of Change

Classwork

47) If a car passes mile-marker 50 in 2 hours and mile-marker 200 in 6 hours, how many miles per hour is the car traveling?

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48) A driver sets the cruise controls at 55 miles per hour. After driving for 3 hours, he passes mile-marker 650. In 2 hours, what mile-marker will he be passing?

49) Dominique earns $10 per hour for tutoring students and is given $15 for gas everyday. Write an equation that represents the situation.

50) Maria spends $200.50 on groceries in a week but earned $4000 total at her last job. Write an equation that represents the situation.

51) John has a company that charges $4/lb. for gourmet candy plus $7 shipping. If Lisa buys 6 lbs. of candy, how much money will she spend?

Homework

52) If a car passes mile-marker 25 in 2 hours and mile-marker 450 in 5 hours, how many miles per hour is the car traveling?

53) A driver sets the cruise controls at 45 miles per hour. After driving for 2 hours, he passes mile-marker 20. In 3 hours, what mile-marker will he be passing?

54) Christina earns $7.50 per hour for tutoring students and is given $50 for gas everyday. Write an equation that represents the situation.

55) Monique spends $400 on groceries in a week but earned $15,000 total at her last job. Write an equation that represents the situation.

56) Timothy has a company that charges $9/lb. for gourmet candy plus $7 shipping. If Janice buys 3 lbs. of candy, how much money will she spend?

Proportional Relationships and Graphing

Classwork

For each problem, draw the graph of the relationship between the two quantities & state what the slope is.

57) A maple tree grows 8 inches each year.

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58) Coconuts are $4.50 per pound.

59) Every 5 days, Lilo receives 6 flowers from Stitch.

60) Barney makes 4 pies an hour.

61) Aladdin takes a carpet ride every 5 days.

62) Speed Racer drives a race every 3 years.

63) Brooke puts $5.00 in her bank account every week.

64) Peyton grades a quiz every 30 seconds.

Homework

65) A palm tree grows 2 inches each year.

66) Pineapples are $2.00 per pound.

67) Every 3 days, Lilo receives 4 flowers from Stitch.

68) Princess Fiona makes 8 puzzles in her tower in 3 hours.

69) Jasmine takes a carpet ride every 3 days.

70) Mach 5 drives a race every 7 days.

71) Hayley puts $20.00 in her bank account every week.

72) Lucas grades a test every 2 minutes and 30 seconds.

Slope & Similar Triangles

Classwork

Find the slope of the hypotenuse from the triangle with the following points.

73) (0,0); (0,4); (7,0)

74) (1,3); (1,7); (-4,3)

75) (-3,2); (-3,3); (-5,3)

76) (1,1); (1,5); (2,5)

77) Find three points that form a triangle that lies on a line with a slope of 3/5.

78) State whether triangle A and triangle B are congruent, similar, or neither.

a. Triangle A: (1,5) (1,9) (3,9) Triangle B: (-3,0) (-3,3) (-1,3)

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b. Triangle A: (2,5) (2,7) (5,7) Triangle B: (-2,2) (4,2) (4,6)

c. Triangle A: (3,4) (1,4) (8,12) Triangle B: (1,-5) (-2,-6) (2,5)

79) Consider a slide. The top of the slide is 7 ft from the ground. The base of the slide is 10 ft from the ladder. What is the slope of the slide? If you were at the base of the slide, and moved 2 feet closer to the slide, how high is the slide at this point? How high off the ground would the slide be if you moved the slide base 2 ft towards where the ladder was? How far from the ladder would the base of the slide need to be placed if you wanted the slide to have a slope of 1/2?

Homework

Find the slope of the hypotenuse from the triangle with the following points.

80) (7,1); (4,0); (7,0)

81) (0,2); (0,6); (-5,2)

82) (-2,3); (-2,4); (-4,4)

83) (-2,-2); (-2,2); (-1,2)

84) Find three points that form a triangle that lies on a line with a slope of 2/5.

85) State whether triangle A and triangle B are congruent, similar, or neither.

a. Triangle A: (6,10) (6,14) (8,14) Triangle B: (-1,2) (-1,5) (1,5)

b. Triangle A: (6,9) (6,11) (9,11) Triangle B: (-6,-9) (-6,-11) (-9,-11)

c. Triangle A: (3,6) (1,4) (1,12) Triangle B: (1,-5) (1,-6) (5,5)

86) Consider a slide. The top of the slide is 4 ft from the ground. The base of the slide is 2.5 ft from the ladder. What is the slope of the slide? How high off the ground would the slide be if you moved

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the slide base .5 ft towards where the ladder was? How far from the ladder would the base of the slide need to be placed if you wanted the slide to have a slope of 1/2?

Parallel and Perpendicular Lines

Classwork

87) What is a line parallel to y = -4/5x + 7?

88) What is a line parallel to y = -4x -4?

89) What is a line parallel to y = x?

90) What is a line parallel to y = 0?

91) What is a line perpendicular to y = 1/2x + 5?

92) What is a line perpendicular to y = -3/4x +4?

93) What is a line perpendicular to y = x?

94) What is a line perpendicular to y = -5x + 2?

Homework

95) What is a line parallel to y = 3/8x + 4?

96) What is a line parallel to y = -2x -7?

97) What is a line parallel to y = 3x?

98) What is a line parallel to y = 2?

99) What is a line perpendicular to y = -1/2x + 1?

100) What is a line perpendicular to y = 3/7x -4?

101) What is a line perpendicular to y = 9x?

102) What is a line perpendicular to y = -11/2x - 16?

Systems: Solve by graphing

Classwork

103) y = -x – 7

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y = 43

x – 7

104) y = - 14 x + 2

y = - 12

x + 3

105) y = -3x – 5y = x + 3

106) y = -2x + 5

y = 13

x – 2

107) y = -4x + 7y = -3x + 3

108) y = 34 x – 3

y = 34

x + 2

109) y = 43 x + 3

y = - 23

x – 3

110) y = 13x + 2

y = -x – 2

111) y = 4x – 1y = -x + 4

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112) y = 3x – 4y = 4x + 10

Homework

113) y = - 32x – 4

y = - 12 + 1

114) y = -2x – 2y = -3x – 6

115) y = x – 2y = x + 2

116) y = 34 x + 1

y = - 12

x – 4

117) y = x – 4y = -x + 2

118) y = -4x – 1y = x – 11

119) y = -3x – 3

y = 12

x + 4

120) y = - 25x + 3

y = 25

x – 1

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121) y = -x – 2

y = - 12x + 2

122) y = x + 5y = -x + 3

Systems: Solve by Substitution

Classwork

123) x = 4y – 9x = y + 3

124) 5x = -2y + 48x = -3y + 20

125) y – 4x = 28y = -2x – 2

126) y + 2x = -12y = x + 15

127) x = -2y – 72x + y = -14

128) x = 5y – 38x = -4y + 16

129) y = 2x + 34x – 2y = 8

130) x = -4y + 8x = 3y + 8

131) 5y + 5x = 85y = 4x – 18

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132) x = y – 12x = 5y – 40

Homework

133) y = -5x + 41-2x = -14 – 2y

134) y = 3x + 6-6x + 2y = 12

135) y – 3x = 0y = -3x – 18

136) x = -3y + 134x – 4y = 20

137) x = -4y + 295x + 2y = 37

138) y = -2x + 115y – 2x = 31

139) 5y – 5x = -15y = -3x + 29

140) -4x = 3y + 32x = -5y – 8

141) y = -3x – 1-4y + x = -9

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142) y = -4x + 17-3y – x = -7

Systems: Solve by Elimination (Addition & Subtraction)

Classwork

143) 3x + y = 365x + y = 56

144) x + 2y = 25x + 3y = 33

145) 3x – 5y = -52x – 5y = -34

146) 2x + 3y = 4-2x + 5y = 60

147) 2x + 2y = 25x – 2y = 40

148) -x + 2y = 14x – 2y = -11

149) 4x – y = 164x + 2y = 16

150) 2x + 5y = 5-2x + y = -23

151) 2x – 2y = -12x – 2y = -13

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152) 5x + 5y = 40-5x + 3y = -40

Homework

153) 4x – y = -24x + 5y = 10

154) 2x + 4y = 10-4x + 4y = 52

155) -3x – 5y = 493x + 4y = -44

156) -4x + 3y = 395x – 3y = -45

157) -5x – 2y = -5-x – 2y = -1

158) x + 5y = -4-x + 2y = -10

159) -4x + 2y = -444x + 4y = 20

160) x + 2y = 4x + 5y = -2

161) 3x – y = -5-3x – 2y = -10

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162) 3x – y = 11-3x – 5y = -71

Systems: Solve by Elimination (Multiply First)

Classwork

163) 5x – 4y = 47-x – 16y = 125

164) 3x – 2y = 33-4x – 4y = 16

165) 2x + y = 214x + 3y = 51

166) -3x + 3y = -2712x + 5y = 108

167) 3x + 4y = 3-12x – y = -57

168) 2x + 5y = -78x + 3y = 57

169) 4x + 3y = 338x + y = 31

170) 3x – 2y = 114x – 8y = 36

171) –x – y = -8-4x + 2y = 22

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172) 2x + y = 0-8x + 4y = 80

Homework

173) –x + y = -5-3x + 4y = -12

174) -2x – y = 2-6x + 3y = -18

175) -2x + 2y = 166x – y = -13

176) -4x – 5y = -93x + 10y = 13

177) 3x – 2y = -266x – 4y = -70

178) x + 5y = -123x + y = 6

179) x + y = 144x – 2y = 2

180) -3x + 3y = -3-12x + 5y = -61

181) 3x + 2y = 27-9x + 4y = -51

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182) 4x + 4y = 202x – 16y = -44

Systems: Choose Your Own Strategy

Classwork

183) –x + 4y = 5x + 4y = 11

184) 3x – y = 74x – 2y = 8

185) 2y + 5x = 35y = 4x – 28

186) 5x – 4y = -39-3x – 4y = -15

187) y = -5x + 594x + y = 49

188) y = x + 6

y = 45 x + 6

189) -2x + 4y = 282x – 3y = -18

190) y = -x + 123y + 3x = 36

191) 2x + 4y = -10

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-4x – 12y = 36

192) –x – 5y = -3-2x + 5y = 9

Systems: Choose Your Own Strategy

Homework

193) -3x + 5y = -3912x – 4y = 60

194) y = 3x – 18y – 3x = -24

195) x + 3y = 16-x + 4y = 5

196) x = -3y – 19x + 5y = -22

197) 3x – 3y = 129x + 2y = 102

198) y = - 43 x + 4

y = 23

x + 10

199) 3x + 2y = 21-3x + 5y = 21

200) –x – y = 7-x + 5y = 19

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201) 4x + y = -28-2x + 2y = 24

202) x = 2y – 7-x + 4y = 17

Writing Systems to Model Situations

Classwork

203) The admission fee at a carnival is $3.00 for children and $5.00 for adults. On the first day 1,500 people enter the fair and $5740 is collected. How many children and how many adults attended the carnival?

204) A builder placed two orders with the hardware store. The first order was for 25 sheets of plywood and 4 boxes of nails and the bill totaled $357. The second order was for 35 sheets of plywood and 2 boxes of nails and the bill totaled $471. The bills do not list the per-item price. What were the prices of one piece of plywood and one box of nails?

Homework

205) Two friends bought some markers and pens. The first bought 4 markers and 5 pens and it cost him $6.71. The second friend bought 5 markers and 3 pens, which cost her $7.12. What is the price for one marker and one pen?

206) The ticket price for the movies is $7.50 for children and $10.50 for adults. One night 825 people bought tickets and $8005.50 was collected from ticket sales. How many children and how many adults bought tickets.

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Answer Key

Tables

Classwork1-5 Answers will vary

Homework6-10 Answers will vary

Slope and y-intercept

Classwork11)

Lines y intercept Slope (+, -, 0 or undefined

A 0 -B 6 +C -5 +D -2 0

12)

13) Lines Equation

E y = 1/2x + 1F y = -2x + 4G x = 8H y = x - 7

Homework

14) Lines y intercept Slope (+, -, 0 or

undefinedI 8 0J 3 -K -1 +L -8 +

15)Lines Equation

M -1N 2O 0P -1/3

16)Lines Equation

M y = -x+5N y = 2xO y = -4P y = -1/3x - 6

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Lines slope

E ½ F -2G UndefinedH 1

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Slope FormulaClasswork17) -1/418) -3019) undefined20) -3/421) -1/222) 623) 5/424) 1/925) 326) 0

Homework

27) -528) -129) 3/230) 031) -332) -133) undefined34) -2.535) ½36) 6/7

Slope Intercept FormClasswork37a) y = -2x+1 37b) y = -1/2x37c) y = -x+137d) y = -2/5x – 137e) y = -3/2x – 3

38) line O39) line M40) line P41) line N

Homework42a) y = 3/2x – 242b) y = x + 142c) y = 2x – 342d) y = 1/2x + 342e) y = x42f) y = 2x

Rate of ChangeClasswork47) 37.5 mph48) mile marker 76049) y = 10x + 15, x being number of hours50) y = -200.50x + 4000, x being number of weeks51) $31

Homework

52) 141.7 mph53) mile marker 15554) y = 7.50x + 50, x being number of hours55) y = -400x + 15,000, x being number of weeks56) $34

Proportional Relationships and GraphingClasswork57) y = 8x58) y = 4.50x59) y = 6/5x60) y = 4x61) y = 1/5x62) y = 1/3x63) y = 5x64) y = 1/30x

Homework65) y = 2x66) y = 2x67) y = 4/3x68) y = 8/3x69) y = 1/3x70) y = 1/7x71) y = 20x72) y = 2/5x

Slopes & Similar TrianglesClasswork73) -4/774) 4/575) -1/276) 477) answers will vary78a) neither78b) similar78c) neither

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43) line L44) line I45) line K46) line J

79) The slope of the slide is 7/10. The slide would be 1.4 ft high. The base of the slide would need to be 14 feet away if you wanted a slope of ½.

Homework80) 1/381) 4/582) -1/283) 484) answers will vary

85a) neither85b) congruent85c) neither

86) Slope of the slide is 8/5. The slide would be .8 ft high. The base of the slide would need to be 8 feet away.

Parallel and Perpendicular LinesClasswork

87 – 94 Answers will vary

Homework95-102 Answers will vary

Systems: Solve by GraphingClasswork103) (0,-7)

104) (4,1)

105) (-2,1)

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106) (3,-1)

107) (4, -9)

108) no solution

109) (-3, -1)

110) (-3, 1)

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111) (1, 3)

112) (-14, -46)

Homework113) (-5, 3.5)

114) (-4,6)

115) no solution

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116) (-4, -2)

117) (3, -1)

118) (2, -9)

119) (-2, 3)

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120) (5, 1)

121) ( -8, 6)

122) (-1, 4)

Systems: Solve by SubstitutionClasswork

123) (7, 4)124) (8,4)125) (-5, 8)126) (-9, 6)127) (-7, 0)128) (-8, 6)129) no solution130) (8, 0)131) (7, 10)132) (-5, 7)

Homework133) (8,1)134) ∞ solutions135) (-3, -9)136) (7, 2)137) (5, 6)138) (2, 7)139) (8, 5)140) (-8, 0)141) (-1, 2)142) (4, 1)

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Systems: Solve by Elimination (Add & Subtract)Classwork143) (10, 6)144) (9, 8)145) (-9, 5)146) (-10, 8)147) (6, -5)148) no solution149) (4, 0)150) (10, -3)151) (1, 7)152) (8, 0)

Homework153) (0, 2)154) (-7, 6)155) (-8, -5)156) (-6, 5)157) (1, 0)158) (6, -2)159) (9, -4)160) (8, -2)161) (0, 5)162) (7, 10)

Systems: Solve by Elimination (Multiply First)Classwork

163) (3, -8)164) (5, -9)165) (6, 9)166) (9, 0)167) (5, -3)168) (9, -5)169) (3, 7)170) (1,4)171) (-1, 9)172) (-5, 10)

Homework173) (8,3)174) (1, -4)175) (-1, 7)176) (1, 1)177) no solution178) (3, -3)179) (5, 9)180) (8, 7)181) (7, 3)182) (2, 3)

Systems: Choose Your Own StrategyClasswork183) (3, 2)184) (3, 2)185) (7, 0)186) (-3, 6)187) (10, 9)188) (0, 6)189) (6, 10)190) ∞ solutions191) (3, -4)192) (-2, 1)

Homework193) (3, -6)194) no solution195) (7, 3)196) (-29/2, -3/2)197) (10, 6)198) (-3, 8)199) (3, 6)200) (-9, 2)201) (-8, 4)202) (3, 5)

Writing Systems to Model SituationsClasswork203) 620 adults, 880 children204) $13 for plywood, $8 for box of nailsHomework205) marker costs $1.19, pen costs $0.39206) 219 children, 606 adults

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Graphing Linear Equations Name:_________________Unit Review PMI - Eighth Grade Date: _________________

Multiple choice questions: choose the correct answer.

1. What is the y-intercept of a line?a. The point at which the line crosses the origin.b. The point at which the line crosses the y-axis.c. The point at which the line crosses the x-axis.d. The point at which the line stops

2. All of the following statements about the slope of a line are true except:a. Slope is rise over run of a line.b. Slope is run over rise.

c. Slope can be negative.d. Slope can be undefined.

3. For the slope intercept form, y = mx+b, the m is:a. Slopeb. y-intercept

c. x-interceptd. line

4. For the slope intercept form, y = mx+b, the b is:a. Slopeb. y-intercept

c. x-interceptd. line

5. The slope is _____ for the line x = -5.a. Positiveb. Negative

c. Zerod. Undefined

6. The slope is _____ for the line y=x.a. Positiveb. Negative

c. Zerod. Undefined

7. The slope is _____ for the line y =-x.a. Positiveb. Negative

c. Zerod. Undefined

8. Given a line with the equation y = -2/3x+5, what would be the slope of the line that is perpendicular to this line?a. -2/3b. 2

c. -3d. 3/2

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9. Given a line with the equation y =-9x+12, what would be the slope of the line that is perpendicular to this line?a. -9b. 1/9

c. -1/9d. 9

10. The line that passes through the points (2, 2) and (2, -2) has a slope that is:a. Positiveb. Negative

c. Zerod. Undefined

11. The line that passes through the points (-10, 2) and (12, 6) has a slope that is:a. Positiveb. Negative

c. Zerod. Undefined

12. What is the slope of the line that passes through the points (8,-2) and (12, -2)?a. -5b. ½

c. Zerod. Undefined

13. What is the slope of the line that passes through the points (-3,0) and (5, 12)?a. 3b. ½

c. -3/2d. 3/2

14. What is the slope of the line that passes through the points (-7,1) and (7,8)?a. ½b. 2

c. -1/2d. -2

15. The following points lie on the line y =2x + 7, except:a. (1, 9)b. (-2, 3)

c. (4, 12)d. (-4, 1)

16. The following points lie on the line y = -2/3x-4, except:a. (0, -4)b. (-3, -2)

c. (-6, 9)d. (-12, 4)

17. If Sarah can make $30 a week babysitting, and she deposits her money into a savings account that originally had $100 dollars, how much will she have after 5 weeks?a. $150b. $100

c. $200d. $250

18. If you were to write an equation for the amount of money Sarah has from question 16, what would be the y-intercept?a. $150b. $100

c. $200d. $250

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19. A car traveling a constant speed of 55 miles an hour passed mile marker 126 on the interstate. After 3 hours of traveling, what mile marker will it have passed?a. Mile marker 391b. Mile marker 290

c. Mile Marker 291d. Mile Marker 165

20. Monique earned $15,000 for her contract job. She spends $250 a week on living expenses. After 6 weeks, how much will she have left?a. $13,000b. $13,500

c. $12,000d. $11,400

21. What is true about the lines y = -x-7 and y = 4/3x-7?a. They have the same y-intercept.b. They are parallel.

c. They are perpendicular.d. They have the same slope.

22. What is true about the lines y = x+2 and y = -x-2?a. They have the same y-intercept.b. They are parallel.

c. They are perpendicular.d. They have the same slope.

23. John raised his candy price to $6 per lb. He also raised shipping prices to $10 per order. Kathy ordered 6 lbs. of candy on Monday, but then she realized she needed more. She placed a separate order of 2 lbs. on Tuesday. How much did she spend on both orders?a. $58.00b. $68.00

c. $70.00d. $78.00

24. Payal made $400 from her last job. Each week, she spends $20 on food. Which equation would represent how much money she has left after x number of weeks?

a. y =20x+400b. y = 20x-400

c. y =-20x+400d. y =-20x-400

25. Suppose Payal had $600 just prior to her last job. Using the information from question 23, which equation will represent how much money she has after x number of weeks?

a. y =20x+1000b. y = 20x-600

c. y =-20x+1000d. y =-20x-600

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Short Constructed Response Questions: Solve each problem, and write the answer on the line.

For questions 26-35 refer to the following graph.

State if the slope is +, -, 0, or undefined for the

following:

26. Line A: _____ 27. Line B: _____28. Line C: _____ 29. Line D: _____ 30. Line E: _____

Write the equation for the following lines:

31. Line A:____________________32. Line B:____________________33. Line C:____________________34. Line D:____________________35. Line E:____________________

Solve the following systems of equations:

36. x = 4y-0, x = y+3 Answer: ____________________37. y =2x+3, 4x-27 = 8 Answer: ____________________38. y = 10x+20, -30x + 3y = 60 Answer: ___________________39. –x-y=-8, -4x+2y = 22 Answer:____________________40. y = 3x-18, y-3x+ -24 Answer: ____________________

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Extended Constructed Response Questions:

41. Consider a slide shaped like a right triangle. The base of the slide is 20 feet away from the ladder. The top of the slide is 8 feet high. Hint: Draw a picture

a. What is the slope of the slide? b. Write an equation for the line that the slide would form.c. Let’s say you were standing at the bottom of the slide, and walked 5 feet closer

to the ladder. How high is the slide at this point?d. If the slide was 22 feet long, what would be the new slope?

42. Bob sells pineapples in a pineapple stand in Lahaina, Hawaii. Today, he has 100 pineapples to sell. Based on his experience, he usually sells about 10 pineapples per hour.

a. Write an equation that represents how many pineapples he can sell in one day.b. Using your equation from part a, draw a graph.c. If he starts selling at 10 a.m., how many pineapples has he sold so far at 2 p.m.?d. What time will he have sold all of his pineapples?

43. Fred placed an order with the furniture store. He ordered metal chairs at $25 each and plastic chairs at $10 each. His order totaled $450.00. There were 30 chairs he ordered. How many of each chair did he order?

a. Write a system of equations that describes this situation, and define your variables.

b. How many of each chair did he order?

44. A group of 148 people is spending five days at a summer camp. The cook ordered 12 pounds of food for each adult and 9 pounds of food for each child. A total of 1,410 pounds of food was ordered.

a. Write a system of equations that describes this situation, and define your variables.

b. Solving the system of equations from part a, find the number of adults and number of children that were at the camp.

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Graphing Linear Equations –Unit Review

Answer Key

1. B2. B3. A4. B5. D6. A7. B8. D9. B10. D11. A12. C13. D14. A15. D16. C17. D18. B19. C20. B

21. A22. C23. B24. C25. C26. Undefined27. 028. Negative29. Positive30. Negative31. x = -732. y = -533. y = -5/2x34. y = x35. y = - 1/4x+836. (4,1)37. No solution38. infinitely many solutions39. (-1,9)40. No solution

41. A. depending on the way the student drew the slide, the slope should be 2/5 or -2/5 B. y=2/5x+8 C. 2 ft off the ground. D. 4/11

42. A. y = -10x + 100 C. 40 pineapples D. 8 p.m.43. A. m = number of metal chairs, p = number of platic chairs, m + p= 30, 25m + 10p = 400

B. Fred ordered 10 metal chairs and 20 plastic chairs.44. A. a = number of adults, c = number of children, a + c =148, 12a + 9c=1,410. B. 26

adults, 122 children

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