Linear_Functions

Graph Explain

100

y=2x +1

Explain how to graph this equation.

First, plot the intercept, (0,1) then go up 2 then right 1. 

200

y=(-2/3)x -7

First, plot y-int, (0,-7) then go down 2 then right 3. 

300

y=4x+8

Explain how to graph this equation.

First, plot (0,8) then use slope, m=4/1, go up 4 the right 1. 

400

y=(1/2)x -6

Explain how to graph this equation.

First, plot (0,-6) then go up 1 then right 2. 

500

y=-3x+5

First, plot (0,5) the go down 3 then right 1. 

Writing Linear Functions

100

Write a linear function in standard form where A=2 B=-4 and C=19

2x-4y=19

200

Write a linear function with a slope of -9 and a y-intercept of 5

f(x)=-9x+5

300

Write a linear function in slope intercept form when slope=3 and y-intercept is 2. 

y=3x+2

400

Write an equation of the line with a slope of 2 and passes through the point (3,5)

y-5=2(x-3)

500

Write the equation of the line with a slope of 3 that passes through the point (1,4)

y-4=3(x-1)

Slope

100

y=2x-12

What is the slope? 

m=2

200

y= (3/5)x -6

m=3/5

300

What is the slope of a vertical line?

undefined 

400

What is the slope of a horizontal line?

m=0

500

Find slope:

(2,3) and (5,7) 

(hint: use slope formula)

slope = 4/3

Intercepts

100

What does the b represent in y=mx+b

y intercept.

200

True or False

In equation, y=2x-4, the y intercept is (0,4)

False

300

What is the y-intercept?

y=1/2x -8

(0,-8)

400

True or False:

y=4(x+2)

The y-intercept is (0,8)

True

500

What is the y-intercept?

y-1=3(x+2)

(hint: write in slope intercept form)

y-int = (0,7)

Modeling with Linear Functions

100

A video rental store charges a $20 membership fee and $2 for each video rented. Write and graph a linear equation (y=mx+b) to model this situation.

y=2x+20

200

A local painter charges a one time fee of $35 plus $15 per day to paint a house. If x = number of days , and y = total cost, write an equation that best represents the situation.

y=35+15x

300

A car rental service charges a $20 transportation fee and $30 dollars an hour to rent a car. Write and graph an equation representing the cost, y, of renting a car for x hours

y=20+30x

400

A local daycare center charges a one time fee of $45 plus $20 per week to watch a child after school. If x = number of weeks , and y = total cost, write an equation that best represents the situation.

y=45+20x

500

In order to join a dancing club, there is a $30 startup fee and a $4 monthly fee. Write an equation in slope-intercept form that models this situation.

y=4x+30