Let f(x) = 2x + 2. solve f^-1(x) when x = 4

Basically, x becomes y an y becomes x
inverses
if f(x)=y, then f⁻¹(y)=x

so what you do is evaluate f(4) and that answer is the x in the f⁻¹(x)

f(4)=2(4)+2
f(4)=8+2
f(4)=10

theefor

f⁻¹(10)=4

if you wanted to find inverse
y=2x+2
x=2y+2
x-2=2y
=y
f⁻¹(x)=

anyway, f⁻¹(10)=4

Y=-2x-6 is the answer