SOLUTION: use inverse operations to write the inverse of f(x)=x/5+2

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Question 265999: use inverse operations to write the inverse of f(x)=x/5+2
Answer by Earlsdon(6294) About Me  (Show Source):
You can put this solution on YOUR website!
Find the inverse of:
f%28x%29+=+%28x%2F5%29%2B2 Substitute y+=+f%28x%29
y+=+%28x%2F5%29%2B2 Now exchange the x and y.
x+=+%28y%2F5%29%2B2 Solve for y.
x-2+=+y%2F5
y+=+5%28x-2%29
y+=+5x-10 Substitute f%5E%28-1%29%28x%29+=+y
highlight%28f%5E%28-1%29%28x%29+=+5x-10%29
Check to see if f%28f%5E%28-1%29%28x%29%29+=+x
f%28f%5E%28-1%29%28x%29%29+=+f%285x-10%29 and...
f%285x-10%29+=+%285x-10%29%2F5%2B2 Simplify the right side.
f%285x-10%29+=+%285x-10%2B10%29%2F5
f%285x-10%29+=+5x%2F5
f%285x-10%29+=+x so...
f%28f%5E%28-1%29%28x%29%29+=+x QED