Answer :
I think you mean the inverse
to find it
switch x and y
solve for y
replace y with f⁻¹(x)
y=5x-10
x=5y-10
x+10=5y
1/5x+2=y
f⁻¹(x)=1/5x+2
to find it
switch x and y
solve for y
replace y with f⁻¹(x)
y=5x-10
x=5y-10
x+10=5y
1/5x+2=y
f⁻¹(x)=1/5x+2