How do you find the inverse of $f(x)= (1/2)x + 4$ and is it a function?

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Answer 1 · 2016-03-21T10:44:00

$y=2x-8$ is the inverse of $y=1/2x+4$ and it is a linear function.

From the given
$y=1/2x+4$

interchange the variables first

$x=1/2y+4$

solve for y in terms of x

$y=2x-8$

let us check using the graphs compared to $y=x$

graph{(y-1/2x-4)(y-2x+8)(y-x)=0[-20,20,-10,10]}

Notice that the line $y=x$ acts as the mirror line. Therefore the equations above are inverses of each other.

God bless.... I hope the explanation is useful.

How do you find the inverse of f(x)= (1/2)x + 4f(x)= (1/2)x + 4 and is it a function?