Question

F(x)=5-4x/15. Find F-1(x)

Answer 1

Substitute f(x)=0

0=5-4x over 15 multiply both sides

0=75-4x move the variable to the left

4x=75 divide both sides

solution x=75 over 4

alternate form is x=18 3 over 4, x=18.75

Explanation: