NAME __________________________________________
DATE ____________ PERIOD _______
Lesson 6 Extra Practice
Equations in y = mx + b Form
Write an equation of a line in slope-intercept form with the given slope and y-intercept.
1. slope: 3; y-intercept: −5
5
4. slope: −7; y-intercept: 2
2. slope: 2; y-intercept: −6
1
5. slope: 2; y-intercept: 7
1
3. slope: −6; y-intercept: 2
3
6. slope: 4; y-intercept: −8
Write an equation in slope-intercept form for each table.
7. x 0 3 6
y
9
8.
5 7 9 11
x −7
y
1
0
7
14
9.
−1 −3 −5
x −2 0 2
y
Write an equation in slope-intercept form for each graph shown.
10.
11.
12.
13.
14.
15.
Course 3 • Chapter 3 Proportional Relationships and Slope
12
4
6 0 −6
Name: _______________________________________ Period: ________________ Date: ____________
Problem Solving for y=mx+b
For Exercises 1 and 2, use the following information. Ace Car Rentals charges $20 per day plus a $10 service
charge to rent one of its compact cars. The total cost can be represented by the equation y = 20x + 10, where x is
the number of days and y is the total cost.
1. Graph the equation. What do the slope and y-intercept represent?
Slope= _____________
This means that ________________
__________________________________
__________________________________
__________________________________
Y-Intercept= _____________
This means that ____________________
__________________________________
__________________________________
2. Explain how to use your graph to determine the total cost of renting a compact car for 7 days. Then determine this cost.
The cost equals _________________ This can be determined by ___________________________________________
_______________________________________________________________________________________________
3. The equation y = 0.2x + 3.5can be used to determine the amount of accumulated snow y in inches x hours after 5 P.M. on
a certain day. Identify the slope and y-intercept of the graph of the equation and explain what each represents.
Slope= __________ This means that ________________________________________________________________
Y-Intercept=__________ This means that _____________________________________________________________
4. Janette’s weekly salary can be represented by the equation y = 500 + 0.4x, where x is the dollar total of her sales for the
week. Identify the slope and y-intercept of the graph of the equation and explain what each represents.
Slope= ___________ This means that _______________________________________________________________
Y-Intercept= __________ This means that ____________________________________________________________