SOLUTION: Finding an inverse formula of f(x) = 9-4x First I replaced f(x) with y: y=9-4x then i switched y with x: x=9-4y then i solved for y x-9 = -4y (x-9)/-4 = y now if i replace

Algebra ->  Finance -> SOLUTION: Finding an inverse formula of f(x) = 9-4x First I replaced f(x) with y: y=9-4x then i switched y with x: x=9-4y then i solved for y x-9 = -4y (x-9)/-4 = y now if i replace      Log On


   

Question 193084: Finding an inverse formula of f(x) = 9-4x
First I replaced f(x) with y: y=9-4x
then i switched y with x: x=9-4y then i solved for y
x-9 = -4y
(x-9)/-4 = y
now if i replace y with f -1(x) will i change the signs as well to (-x+9)4? or am I completely wrong with my calculations?
Answer by Earlsdon(6294) About Me  (Show Source):
You can put this solution on YOUR website!
You've done the math correctly and, no, you do not have to change the sign at the end!
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