NAME
DATE
4-7
PERIOD
Practice
Inverse Linear Functions
Find the inverse of each relation.
1. {(-2, 1), (-5, 0), (-8, -1), (-11, 2)}
2. {(3, 5), (4, 8), (5, 11), (6, 14)}
{(1, -2), (0, -5), (-1, -8), (2, -11)}
{(5, 3), (8, 4), (11, 5), (14, 6)}
3. {(5, 11), (1, 6), (-3, 1), (-7, -4)}
4. {(0, 3), (2, 3), (4, 3), (6, 3)}
{(11, 5), (6, 1), (1, -3), (-4, -7)}
{(3, 0), (3, 2), (3, 4), (3, 6)}
Graph the inverse of each function.
5.
8
6.
y
−4
7.
8
4
4
−8
y
8
4
O
8x
−8
−4
y
4
4
O
8x
−8
−4
4
O
−4
−4
−4
−8
−8
−8
8x
Find the inverse of each function.
6
8. f (x) = −
x-3
5
6
11. f (x) = 3(3x + 4)
x
−
-4
3
-1
=
f (x)
−
3
3x - 1
10. f (x) = −
6
6x + 1
f -1(x) = −
3x - 2
f -1(x) = −
4
3
2x - 3
13. f (x) = −
7
12. f (x) = -5(-x - 6)
7x + 3
f -1(x) = −
x
f -1(x) = −
-6
5
4
Write the inverse of each equation in f -1(x) notation.
13. 4x + 6y = 24
24 - 6x
f -1(x) = −
4
16. 5x + 8y = 40
40 - 8x
f -1(x) = −
5
14. -3y + 5x = 18
15. x + 5y = 12
3x + 18
f -1(x) = −
f -1(x) = -5x + 12
5
17. -4y - 3x = 15 + 2y
18. 2x - 3 = 4x + 5y
-5x - 3
f -1(x) = −
f -1(x) = -2x - 5
2
19. CHARITY Jenny is running in a charity event. One donor is paying an initial amount of
$20.00 plus an extra $5.00 for every mile that Jenny runs.
a. Write a function D(x) for the total donation for x miles run. D(x) = 5x + 20
x - 20
b. Find the inverse function, D -1(x). D -1(x) = −
5
c. What do x and D -1(x) represent in the context of the inverse function? x represents
the total donation and P -1(x) represents the number miles run.
Chapter 4
46
Glencoe Algebra 1
Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.
5
f -1(x) = −
(x + 3)
4x + 2
3
9. f (x) = −