Question

Let f(x) = 7x - 13. Find f-1(x).

Answer 1

$f(x)=7x-13 \\ \\ y=7x-13 \ \ \ |+13 \\ y+13=7x \ \ \ |\div 7 \\ x=\frac{1}{7}y+\frac{13}{7} \\ \\ \boxed{f^{-1}(x)=\frac{1}{7}x+\frac{13}{7}}$