Answer:
3/2
Step-by-step explanation:
f(x)=2x+5
first find inverse (write it without f(x))
y = 2x + 5
x = 2y + 5 (swap the variables, now solve for y)
- 5 -5
x - 5 = 2y
/2 /2 (divide both sides by 2)
(x-5)/2 = y
so f-1(x) = (x-5)/2
f-1(8) = (8-5)/2
= (3)/2
f-1(8) = 3/2
