College

Given the function [tex]f(x) = -5x^2 - x + 20[/tex], find [tex]f(3)[/tex].

A. -28
B. -13
C. 62
D. 64

Answer :

To find [tex]\( f(3) \)[/tex] for the function [tex]\( f(x) = -5x^2 - x + 20 \)[/tex], follow these steps:

1. Substitute [tex]\( x = 3 \)[/tex] into the function:
[tex]\( f(3) = -5(3)^2 - (3) + 20 \)[/tex].

2. Calculate [tex]\( 3^2 \)[/tex]:
[tex]\( 3^2 = 9 \)[/tex].

3. Multiply by [tex]\(-5\)[/tex]:
[tex]\(-5 \times 9 = -45\)[/tex].

4. Perform the subtraction:
Take [tex]\(-45\)[/tex] and subtract [tex]\(3\)[/tex]:
[tex]\(-45 - 3 = -48\)[/tex].

5. Add [tex]\(20\)[/tex]:
[tex]\(-48 + 20 = -28\)[/tex].

Therefore, [tex]\( f(3) = -28 \)[/tex].