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 the value of the function [tex]\( f(x) = -5x^2 - x + 20 \)[/tex] at [tex]\( x = 3 \)[/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. Subtract the value of [tex]\( x \)[/tex]:

[tex]\[
-45 - 3 = -48
\][/tex]

5. Add 20 to the result:

[tex]\[
-48 + 20 = -28
\][/tex]

So, the value of the function [tex]\( f(x) \)[/tex] at [tex]\( x = 3 \)[/tex] is [tex]\(-28\)[/tex].