SOLUTION: what is the inverse of f(x)=5-2x?

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Question 1188797: what is the inverse of f(x)=5-2x?
Found 3 solutions by MathLover1, Alan3354, greenestamps:
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!

to find the inverse of f%28x%29=5-2x, recall that f%28x%29=y
y=5-2x........swap variables
x=5-2y........solve for y
2y=5-x
y=5%2F2-%281%2F2%29x

the inverse is f'%28x%29=-%281%2F2%29x%2B5%2F2

Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
what is the inverse of f(x)=5-2x?
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y = 5 - 2x
Sway the x and y
x = 5 - 2y
Solve for y.
2y = 5 - x
y = 2.5 - (x/2) is the inverse.

Answer by greenestamps(13200) About Me  (Show Source):
You can put this solution on YOUR website!


For relatively simple functions like this, you can also find the inverse by using the concept that an inverse function "un-does" what the function does.

The given function does the following to the input:
(1) multiply by -2
(2) add 5

The inverse function needs to perform the opposite operations, in the opposite order:
(1) subtract 5
(2) divide by -2

The inverse function is

y=(x-5)/(-2)

or

(-1/2)x+5/2