SOLUTION: How do I get the inverse y=f(x) y= 5x-9/3x-7 After I multiply the reciprocal and wipe out 3x-7 on the right, I just don't know how to do the left side.

Algebra ->  Inverses -> SOLUTION: How do I get the inverse y=f(x) y= 5x-9/3x-7 After I multiply the reciprocal and wipe out 3x-7 on the right, I just don't know how to do the left side.       Log On


   

Question 1008364: How do I get the inverse y=f(x)
y= 5x-9/3x-7
After I multiply the reciprocal and wipe out 3x-7 on the right, I just don't know how to do the left side.
Found 2 solutions by josgarithmetic, stanbon:
Answer by josgarithmetic(39620) About Me  (Show Source):
You can put this solution on YOUR website!
Assuming that you really have f%28x%29=%285x-9%29%2F%283x-7%29, because grouping properly is important,...

Let g(x) be the inverse of f(x).
g%28f%28x%29%29=f%28g%28x%29%29=x

Using your definition for f, and letting input for f be g(x), you expect
%285g%28x%29-9%29%2F%283g%28x%29-7%29=x.
Solve for g(x).

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
How do I get the inverse y=f(x)
y= 5x-9/3x-7
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1st: Interchange x and y to get:
x = (5y-9)/(3y-7)
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2nd:: Solve for "y"::
Cross-multiply to get:
3xy-x = 5y-9
---
3xy-5y = x-9
----
y(3x-5) = x-9
-----
y = (x-9)/(3x-5)
----
That is the inverse.
Cheers,
Stan H.
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