Question

Find g^−1 (x) when g(x) = 3/5 x −9.

5/3x − 1/9
5/3 x + 9
−3/5 x+ 9
5/3 x + 15

Answer 1

5/3 x + 15

Explanation:

The inverse of a function is the reflection across the line y = x. As such, algebraically it is found by switching y and x in the equation and isolating to solve for y.

g(x) = 3/5 x - 9

x = 3/5 y - 9

x + 9 = 3/5 y

5(x+9) = 3y

(5x + 45)/3 = y

5/3x + 15 = y