ALGEBRA 1Chapter 5

ENTRY TASK 01/03/2011 Graph the following equation using

slope-intercept form:

On the back of your paper evaluate the following:

54 xy

8 7 )5)(3(

SECTION 5.1 Objective: Use slope-intercept form to

write the equation of a line. Model real-life situations with a linear function.

PE’s: A1.4.B Write and graph an equation for a line given the

slope and y-intercept, the slope and a point on the line, or two points on the line and translate between forms of linear equations.

A1.4.C Identify and interpret the slope and intercepts of a linear function, including equations for parallel and perpendicular lines.

A1.4.E Describe how changes in the parameters of linear functions and functions containing an absolute value of a linear expression affect their graphs and the relationships the represent.

HOMEWORK

Pg. 276 #1-11

ENTRY TASK 01/05/2011 Write an equation that represents the

following situation.Bobby’s Car Rentals rents cars for a base

fee of $150 and then charges $0.20 per mile after that.

How much will it cost to rent a car to travel to Seattle, which is 300 miles away?

SECTION 5.2 Objective: Use slope and any point on a

line to write an equation of the line

WRITING AN EQUATION USING SLOPE AND ONE POINT Write an equation for the line that passes

through the point (6, -3) and has a slope of -2.

Do problems 1-15odd on homework

ENTRY TASK 01/06/2011 Write an equation for the line with slope

-3 and passing through the point (-2, 8)

Use the distributive property to simplify the following:

yyy )23(2

WRITING EQUATIONS OF PARALLEL LINES

Write an equation for the line that is

parallel to and passes

through the point (-2, 1).

If two lines are parallel they have the

same slope

do problems 16-18

23

2 xy

WRITING EQUATIONS FOR REAL LIFE PROBLEMS VACATION TRIPS Between 1985 and

1995, the number of vacation trips in the United States taken by United States residents increased by about 26 million per year. In 1993, United States residents went on 740 million vacation trips within the United States.

a. Write a linear equation that models the number of vacation trips y (in millions) in terms of the year t. Let t be the number of years since 1985.

b. Estimate the number of vacation trips in the year 2005.

Do problems 19-24

ENTRY TASK 01/10/11 Find the slope of the line that passes

through the points (3,6) and (-2,-1)

Graph a line with the above slope that goes through the point (2,-1)

Solve the following equation for y:

7)23(2 yy

SECTION 5.3 Objective: Write an equation of a line

given two points on the line

GRAPHING USING TWO POINTS Step 1- find the slope of the two points

using

Step 2- use the slope and one of the points to find the y-intercept

Step 3- write the equation using

12

12

xx

yyslope

bmxy

HOMEWORK Worksheet 5.3B finish 1-11 for

tomorrow, whole worksheet due Wednesday

ENTRY TASK 01/11/11 Find an equation of the line that goes

through the points (4,5) and (-1,-2).

Solve the following equation for a:

6523 aa

PERPENDICULAR LINES Perpendicular lines are lines that cross

at a right angle (90 degrees)

If two lines are perpendicular, then their slopes are the opposite reciprocals of each other

If the slope of a line is then the slope

of a perpendicular line is

3

4

4

3

HOMEWORK Worksheet 5.3B whole thing due

tomorrow

ENTRY TASK 01/12/2011 complete the mini quiz for section 5.3

SECTION 5.4 Objective: Find a linear equation that

approximates a set of data points. Determine whether there is a positive or negative correlation in a set of real life data.

FITTING A LINE TO DATA Best-fit line- A line that represents a

collection of data, even if you can’t draw a line through all of the points

Sometimes there is no line of best fit

CORRELATIONo Best-fit line- A line that

represents a collection of data, even if you can’t draw a line through all of the points. Sometimes there is no line of best fit

Positive correlation- when the line of best fit has a positive slope

Negative correlation- when the line of best fit has a negative slope

No correlation- when there is no good line of best fit

STEPS FOR FINDING THE LINE OF BEST FIT Step 1: Draw the line of best fit.

Step 2: pick two points on the line.

Step 3: use what we learned in 5.3 to make an equation for the line.

ENTRY TASK 01/14/2011 Figure out your neighbor’s age in months,

height in inches, forearm length in inches and math grade by percent. You may need a ruler.

Choose one partner to go up to the board and record your findings.

For example, my stats are: 68 inches tall 9 inch forearm length 284 months old 97% in freshman algebra

OUR DATA Pick one of the following to make a

scatter plot of: forearm vs. height age vs. grade Forearm vs. grade Age vs. height

After you are done making a scatter plot, see if you can find a line of best fit.

Note: make sure you use tails plus

ENTRY TASK 01/18/2011 Think back to the activity that we did on

Friday. 1.) which sets of data have a positive

correlation? Negative? none?

2.) what do you think the correlation would be between forearm and age? Grade and height?

3.) what are some other collections of data that might have correlations? Give an example of a positive correlation, negative correlation and no correlation.

SECTION 5.5 Objective: use point-slope form to write

an equation of a line. Use point slope form to model a real-life situation.

POINT-SLOPE FORM The point-slope form of the equation of

the non-vertical line that passes through a given point (x1, y1) with a slope of m is

)( 11 xxmyy

HOMEWORK 5.5 practice B

ENTRY TASK 01/19/2011 Write the equation of the line that goes

through the points (-1,-3) and (-2,-5) in point-slope form.

Rewrite the equation in slope-intercept form and state the y-intercept.

ENTRY TASK 01/20/2011 I walk at a rate of 4 miles per hour. Write

a linear equation to model the distance I am from my house if after 3 hours of walking I am 20 miles from home.

How far away from home was I when I started walking?

SECTION 5.6 Objective: Write a linear equation in

standard form. Use the standard form of an equation to model a real life situation.

STANDARD FORM The standard form of a linear equation

is:

where A, B, and C are real numbers.

CByAx

EXAMPLE Write an equation in standard form for

the line that passes through the point (-4,3) and has a slope of -2.

EXIT TASK List three different basic forms of a

linear equation.

ENTRY TASK 01/21/2011 Take a copy of the chapter 4 cumulative

review worksheet and start working on it.

ENTRY TASK 01/23/2011 I am driving to Seattle, which is about

226 miles away. I leave at 6:30am and get to Ellensburg at 8:30am and Ellensburg is 120 miles from Kennewick.

Write an equation to represent this situation and draw a graph to represent it.

ENTRY TASK 01/31/2011 List and write out the three different

forms of a linear equation

ENTRY TASK CONT. 01/31/11 You are buying $48 worth of lawn seed

that consists of two types of seed. One type is a quick growing rye grass that costs $4 per pound, and the other type is a higher-quality seed that costs $6 per pound.

1.) Write an equation that represents the different amounts of $4 seed, x, and $6 seed, y, that you can buy.

2.) rewrite the equation from 1 in slope-intercept form.

3.) Graph the equation.

HOMEWORK Pg. 311 #1-15odd, 16&17

ENTRY TASK 02/03/11 5.5 standardized test practice

SECTION 5.7 Objective: Determine whether a linear

model is appropriate. Use a linear model to make a real-life prediction.

LINEAR MODELS Data that can be represented by a linear

model should increase or decrease at a mostly constant rate.

Linear interpolation- a method of estimating the coordinates of a point that lies between two given data points.

Linear extrapolation- a method of estimating the coordinates of a point to the right or left of all of the given data points.

HOMEWORK 5.7B #1-10

ENTRY TASK 02/04/11 Grab a copy of chapter 5 test. On the back of it write:

1.) the three forms of a linear equation

2.) the two formulas for slope.

HOMEWORK Review worksheet