This set of points is on the graph of a function.

What is the inverse of f(x)=4x+3?

What is the inverse of the function?

f(x) = 1/4x + 10

jbouyer
Dec 4, 2017

#1**+1 **

The inverse will have reverse coordinates.....so the points on the inverse are

(-8, -2), (9, 0)

f(x) = 4x + 3

For f(x), write y

y = 4x + 3 subtract 3 from both sides

y - 3 = 4x divide both sides by 4

[ y - 3 ] / 4 = x swap x and y

[x - 3] / 4 = y for y, write f^{-1}(x)

f^{-1} (x) = (1/4)x - 3/4

f(x) = (1/4)x + 10

y = (1/4)x + 10

y - 10 = (1/4)x multiply both sides by 4

4y - 40 = x

4x - 40 = y

f^{-1}(x) = 4x - 40

CPhill
Dec 4, 2017