SOLUTION: Find the inverse function of f. f(x)=(4x-5)/(7x-9) , x not equal to 9/7

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Question 469417: Find the inverse function of f.
f(x)=(4x-5)/(7x-9) , x not equal to 9/7
Answer by robertb(5830) About Me  (Show Source):
You can put this solution on YOUR website!
Let y+=+%284x-5%29%2F%287x-9%29
Solve for x in terms of y.
==> 7yx - 9y = 4x - 5
==> 7yx - 4x = 9y - 5
==> (7y - 4)x = 9y - 5
==> x+=+%289y+-+5%29%2F%287y+-+4%29
Interchange x and y:
==> y+=+%289x+-+5%29%2F%287x+-+4%29
Hence ==> f%5E%28-1%29%28x+%29=+%289x+-+5%29%2F%287x+-+4%29