If [tex]f(x) = 5x + 40[/tex], what is [tex]f(x)[/tex] when [tex]x = -5[/tex]?

A. [tex]\(-9\)[/tex]
B. [tex]\(-8\)[/tex]
C. [tex]\(7\)[/tex]
D. [tex]\(15\)[/tex]



Answer :

To find [tex]\( f(x) \)[/tex] when [tex]\( x = -5 \)[/tex] for the function [tex]\( f(x) = 5x + 40 \)[/tex], follow these steps:

1. Substitute [tex]\( x = -5 \)[/tex] into the function:
[tex]\[ f(-5) = 5(-5) + 40 \][/tex]

2. Perform the multiplication inside the parentheses:
[tex]\[ 5 \cdot -5 = -25 \][/tex]

3. Now, add the result to 40:
[tex]\[ -25 + 40 = 15 \][/tex]

Therefore, [tex]\( f(-5) = 15 \)[/tex].

Among the options provided:
- [tex]\(-9\)[/tex]
- [tex]\(-8\)[/tex]
- [tex]\(7\)[/tex]
- [tex]\(15\)[/tex]

The correct answer is [tex]\( 15 \)[/tex].