High School

Let [tex]f(x) = 3x^2 - 4[/tex] and [tex]g(x) = 3x + 4[/tex].

Find [tex]f(-4)[/tex].

A. 44
B. -10
C. -52
D. -44

Answer :

To solve the problem of finding [tex]\( f(-4) \)[/tex] for the function [tex]\( f(x) = 3x^2 - 4 \)[/tex], follow these steps:

1. Understand the function: [tex]\( f(x) = 3x^2 - 4 \)[/tex] is a quadratic function.

2. Substitute the given value into the function: We need to evaluate the function at [tex]\( x = -4 \)[/tex].

3. Perform the calculation:
- Substitute [tex]\(-4\)[/tex] into the function: [tex]\( f(-4) = 3(-4)^2 - 4 \)[/tex].
- First, calculate [tex]\((-4)^2\)[/tex], which is [tex]\(16\)[/tex].
- Multiply [tex]\(16\)[/tex] by [tex]\(3\)[/tex]: [tex]\(3 \times 16 = 48\)[/tex].
- Subtract [tex]\(4\)[/tex] from [tex]\(48\)[/tex]: [tex]\(48 - 4 = 44\)[/tex].

4. Result: Therefore, [tex]\( f(-4) = 44 \)[/tex].

So, the correct answer is [tex]\( 44 \)[/tex].