$100 $200 $300 $400 $500 $200 $300 $400 $500 geometric mean pythagorean thm. special right triangles...
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$100 $100 $100 $100 $100
$200
$300
$400
$500
$200 $200 $200 $200
$300 $300 $300 $300
$400 $400 $400 $400
$500 $500$500 $500
Geometric mean Pythagorean Thm.
Special Right Triangles
Law of Sines and Cosines
TrigonometryAngles of elevation and depression
Geometric Mean and the Pythagorean Theorem for $100
Solve for b:
12cm
20cmb
Answer
Pythagorean Theorem: a2 + b2 = c2
122 + b2 = 202
144 + b2 = 400B2 = 256B = 16cm
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Geometric Mean and the Pythagorean Theorem $200
Find the geometric mean between 32 and 2
Answer
x = √(32*2) = √(64) = 8
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Geometric Mean and the Pythagorean Theorem for $300
List three Pythagorean triples
Answer
Answers may vary:
3,4,5
6,8,10
5,12,13
20,48,52
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Geometric Mean and the Pythagorean Theorem for $400
Solve for a
Answer
Back
Based on theorem 7.2, a is the geometric mean of 8 and 6, so
a2 = 8*6
a2 = 48
a = 6.93
Geometric Mean and the Pythagorean Theorem for $500
In triangle ABC, solve for the length of a
Based on Theorem 7.3, AC/AB = AB/Ad
So, (29+21)/(a) = (a)/(21)50/a = a/21a2 = 1050a = 32.4
Answer
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Special Right Triangles for $100
Draw and label the sides of a 45-45-90 right Triangle
Answer
45-45-90 Right Triangle:
Backx
x√(2)x
90° 45°
45°
Special Right Triangles for $200
Draw and label the sides of a 30-60-90 right Triangle
Answer
30-60-90 Right Triangle
Backx
2xx√(3)
60°
30°
90°
Special Right Triangles for $300
If in triangle ABC, AB = 10,
BC = 12 and CA = 9, which angle has the greatest measure?
Answer
Angle A has the greatest measure because it is opposite side BC, which is the longest side.
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Special Right Triangles for $400
Solve for x and y
Answer
Back
Since the triangle is a 30-60-90,
30√(2) = 2y x = y√(3)
y = 15√(2) x = 15√(2)√(3)
x = 15√(6)
Special Right Triangles for $500
Solve for x and y
Answer
Back
Since the triangle is a 45-45-90
y = 7 (isosceles triangle so the legs are the same length)
x = 7√(2)
Trigonometry for $100
List the three basic trigonometry functions and what they equal
Sin (x) = opposite hypotenuse
Cos (x) = adjacent hypotenuse
Tan (x) = opposite
adjacent
Answer
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Trigonometry for $200
Evaluate:
Sin (30)
Answer
Back
Sin (30) = 0.5
Trigonometry for $300
Evaluate cos(x):
15
2520
90° x°
15 is the adjacent side to x
20 is the side opposite of x
25 is the length of the hypotenuse
Cos(x) = adjacent/hypotenuse
So, cos(x) = (15/25) = 3/5
Answer
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Trigonometry for $400
Solve for x:
12
22
90°
x°
We are given the opposite (12) and the adjacent (22) sides to x, so we will use tangent. Since we are solving for the angle, we use tan-1
tan-1(12/22) = x
x = 28.6°
Answer
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Trigonometry for $500
Write the ratios for sin(x) and cos(x)
Triangle XYZ is a right triangle, so the trig functions apply
From angle X,
√(119) is the opposite side
5 is the adjacent side
12 is the hypotenuse
sin(x) = opp/hyp = √(119)/12
cos(x) = adj/hyp = 5/12
Answer
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Angles of Elevation and Depression for $100
A person is standing at point A looking at point B. Does this represent an angle of elevation or depression?
Answer
Back
Angle of depression because they are looking down from the horizontal
Angles of Elevation and Depression for $200
Draw an example of an angle of elevation. Label the angle A
Answer
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A
Angles of Elevation and Depression for $300
A person stands at the top of the tower and looks down at their friend who is standing 18yds from the base of the tower. If the angle of depression is 30 degrees, how tall is the tower?
Answer
Back
Tan(30) = x/18
18*tan(30) = x
x = 10.4 yds
Angles of Elevation and Depression for $400
An airplane over the Pacific sights an atoll at an angle of depression of 5. At this time, the horizontal distance from the airplane to the atoll is 4629 meters. What is the height of the plane to the nearest meter?
Answer
Back
tan(5) = x/4629m
4629*tan(5) = x
x = 405m
Angles of Elevation and Depression for $500
To find the height of a pole, a surveyor moves 140 feet away from the base of the pole and then measures the angle of elevation to the top of the pole to be 44. To the nearest foot, what is the height of the pole?
Answer
Back
140 ft.
x
44°
tan(44) = x/140
140*tan(44) = x
135ft = x
The Laws of Sines and Cosinesfor $100
Write out the law of sines
Answer
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The law of sines:
Sin(A) = Sin(B) = Sin(C) a b c
The Laws of Sines and Cosinesfor $200
Write out the law of cosines
Answer
Back
Law of cosines:
A2 = B2 + C2 – 2BC*cos(a)
B2 = A2 + C2 – 2AC*cos(b)
C2 = A2 + B2 – 2AB*cos(c)
The Laws of Sines and Cosinesfor $300
In triangle ABC, AB = 8, BC = 12 and the m<A = 62 degrees. Solve for m<C.
A 62°
B
C
8 12
Sin(A) = Sin(B) = Sin(C) a b c
Sin(62) = Sin(C) 12 8
8(.0735789661) = sin(c)
sin-1(.5886) = c
c = 36.06°
Answer
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The Laws of Sines and Cosinesfor $400
In triangle ABC, AB = 5, BC = 10 and the m<B = 40 degrees. Solve for AC.
A
40°B
5 10
C
Answer
Back
B2 = A2 + C2 – 2AC*cos(b)B2 = 102 + 52 – 2(10)(5)*cos(40)B2 = 125 – 100cos(40)B2 = 48.396B = 7
The Laws of Sines and Cosinesfor $500
In triangle ABC, AB = 8, BC = 6 and the AC = 13. Solve for m<A.
A
B
8 6
C13
Answer
Back
A2 = B2 + C2 – 2BC*cos(a)62 = 132 + 82 – 2(13)(8)*cos(a)36 = 233 – 208cos(a)-197 = -208cos(a)0.9471 = cos (a)cos-1(0.9471) = aa = 18.7°