Question

the function f(x) is invertible. find $f^{-1}(70)$.

x	f(x)
67	90
68	-90
69	70
70	-48

$f^{-1}(70) = \square$

Explanation:

Step1: Recall inverse function definition

The inverse function \( f^{-1}(y) \) gives the \( x \) such that \( f(x) = y \). So we need to find \( x \) where \( f(x) = 70 \).

Step2: Look at the table

From the table, when \( x = 69 \), \( f(x) = 70 \).

Answer:

69