SOLUTION: Find the inverse of f (x)=x-7/-3x-4

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Question 1006388: Find the inverse of f (x)=x-7/-3x-4
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!

f+%28x%29=%28x-7%29%2F%28-3x-4+%29
recall f+%28x%29=y
y=%28x-7%29%2F%28-3x-4+%29...to find inverse, first swap x and y
x=%28y-7%29%2F%28-3y-4+%29....now solve for y
x%28-3y-4+%29=%28y-7%29
-3xy-4x+=y-7
7-4x+=y%2B3xy
7-4x+=y%281%2B3x%29
y=%287-4x%29%2F%281%2B3x%29+
so, inverse is
f’x=%287-4x%29%2F%283x%2B1%29+