Question

use the following function rule to find f(28).
f(x) = 2\sqrt{77 - x}
f(28) = \square

Explanation:

Step1: Substitute x = 28 into the function

We have \( f(x) = 2\sqrt{77 - x} \), so when \( x = 28 \), we substitute it into the function: \( f(28)=2\sqrt{77 - 28} \)

Step2: Calculate the value inside the square root

First, calculate \( 77 - 28 = 49 \), so now the function becomes \( f(28)=2\sqrt{49} \)

Step3: Calculate the square root and then multiply

Since \( \sqrt{49}=7 \), then \( f(28)=2\times7 = 14 \)

Answer:

14