SOLUTION: f(x)=2x+8, Find f>-1(3)

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Question 551203: f(x)=2x+8, Find f>-1(3)
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
f(x)=2x+8

y=2x+8

x=2y+8

x-8=2y

(x-8)/2=y

y=(x-8)/2

f^(-1)(x) = (x-8)/2

f^(-1)(3) = (3-8)/2

f^(-1)(3) = -5/2