Step-by-step explanation:
Given Function
f(x) = 2.5x + 150
f^-1(x) = ?
Let y = f(x)
y = 2.5x + 150
Interchanging the role of x and y we get,
x = 2.5y + 150
x - 150 = 2.5y
y = (x - 150) / 2.5
So therefore
f^ -1(x) = (x - 150) / 2.5
Hope it will help :)