Answer:
see explanation
Step-by-step explanation:
let y = f(x) then rearrange making x the subject
y = 2x - 10 ( add 10 to both sides )
y + 10 = 2x ( divide both sides by 2 )
[tex]\frac{y+10}{2}[/tex] = x
Change y back into terms of x
[tex]f^{-1}[/tex] (x) = [tex]\frac{x+10}{2}[/tex]