SOLUTION: Find f^-1(x). f(x) = 3/4x - 6/7

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Question 83402: Find f^-1(x).
f(x) = 3/4x - 6/7
Answer by rapaljer(4671) About Me  (Show Source):
You can put this solution on YOUR website!
I like to use a two step method for finding the inverse of a function:
Step 1: Interchange the x and y. Once you interchange the variables, this y becomes the y that represents f%5E-1%28x%29

Step 2: Solve for y.

Begin by writing this f(x) in notation of y:
f%28x%29+=+%283%2F4%29x+-+6%2F7
y+=+%283%2F4%29x+-+6%2F7

Step 1:
y+=+%283%2F4%29x+-+6%2F7
x+=+%283%2F4%29y+-+6%2F7

Step 2:
x+=+%283%2F4%29y+-+6%2F7

Clear fractions:
28x+=+21y-24
28x%2B24=+21y+
%2828x%2B24%29%2F21=y

f%5E-1%28x%29+=+%2828x%2B24%29%2F21

R^2 at SCC