Question

the inverse of the function $f(x) = \frac{1}{2}x + 10$ is shown.
$h(x) = 2x-\square$
what is the missing value?
○ 1
○ 5
○ 10
○ 20

Explanation:

Step1: Set $y = f(x)$

$y = \frac{1}{2}x + 10$

Step2: Swap $x$ and $y$

$x = \frac{1}{2}y + 10$

Step3: Solve for $y$, subtract 10

$x - 10 = \frac{1}{2}y$

Step4: Multiply by 2 to isolate $y$

$y = 2(x - 10) = 2x - 20$

Answer:

D. 20