Name ________________________________________ Date __________________ Class __________________
Using Functions to Solve One-Variable Equations
LESSON
7-2
Practice and Problem Solving: C
Use the following for 1–5.
DJ A charges $75.30 plus $12.50 per hour. DJ B charges $52.90 plus
$18.10 per hour. When will their charges be equal?
1. Write a one-variable equation for the charges of DJ A.
f(x) = ___________________________
2. Write a one-variable equation for the charges of DJ B.
g(x) = ___________________________
3. Complete the table for f(x) and g(x).
Hours
f(x)
g(x)
0
1
2
3
4
5
4. Use a graph to solve for x. Plot f(x) and g(x) on the graph below. Find
the intersection.
5. After how many hours will the two DJs charge the same
amount? ____________
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4.
LESSON 7-2
Practice and Problem Solving: A/B
1. f(x) = 20x + 90
2. g(x) = 30x + 50
3.
x
f(x)
g(x)
0
90
50
1
110
80
2
130
110
3
150
140
1. f(x) = 4x + 15
4
170
170
2. g(x) = 2x + 25
5
190
200
5. 4 hours
Practice and Problem Solving:
Modified
4.
x
f(x)
g(x)
0
15
25
1
19
27
2
23
29
3
27
31
4
31
33
5
35
35
4.
5. 4 hours
6 a. f(x) = 600 − 75x
b. 8 months
Practice and Problem Solving: C
1. f(x) = 12.5x + 75.30
2. g(x) = 18.10x + 52.90
3.
X
f(x)
g(x)
0
75.30
52.90
1
87.80
71.00
2
100.30
89.10
1. x = −5
3
112.80
107.20
2. x = 3
4
125.30
125.30
5
137.80
143.40
5. 5 hours
Reading Strategies
3. x = 2
4. x = −1.5
Success for English Learners
1. f(3) = 3(3) + 7 = 16 and g(3) = 7(3) − 5 = 16
2. 2
3. 2
Original content Copyright © by Houghton Mifflin Harcourt. Additions and changes to the original content are the responsibility of the instructor.
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