How do you find the inverse of #f(x) =1/4x+7#?

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Answer 1 · 2015-06-19T21:53:00

Write #y = 1/4x+7#

then rearrange to find #x = 4(y-7)#, so the inverse function is:

#f^-1(y) = 4(y-7)#

Let #y = f(x) = 1/4x+7#

Subtract #7# from both ends to get:

#y-7 = 1/4x#

Multiply both sides by #4# to get:

#x = 4(y-7)#

This defines #x# in terms of #y# in such a way that the equation #y = 1/4x+7# is satisfied, so it defines the inverse function:

#f^-1(y) = 4(y-7)#