If [tex]$f(x) = |x| + 9$[/tex] and [tex]$g(x) = -6$[/tex], which describes the range of [tex]$(f+g)(x)$[/tex]?

A. [tex]$(f+g)(x) \geq 3$[/tex] for all values of [tex]$x$[/tex]
B. [tex]$(f+g)(x) \leq 3$[/tex] for all values of [tex]$x$[/tex]
C. [tex]$(f+g)(x) \leq 6$[/tex] for all values of [tex]$x$[/tex]
D. [tex]$(f+g)(x) \geq 6$[/tex] for all values of [tex]$x$[/tex]



Answer :

To solve the problem, let's start by defining the functions and determining their combined effect.

1. Given functions:
- [tex]\( f(x) = |x| + 9 \)[/tex]
- [tex]\( g(x) = -6 \)[/tex]

2. Sum of the functions:
[tex]\[ (f + g)(x) = f(x) + g(x) \][/tex]
Substituting the given functions:
[tex]\[ (f + g)(x) = (|x| + 9) + (-6) \][/tex]
Simplifying:
[tex]\[ (f + g)(x) = |x| + 9 - 6 = |x| + 3 \][/tex]

3. Analyzing the expression [tex]\( |x| + 3 \)[/tex]:
- [tex]\( |x| \)[/tex] represents the absolute value of [tex]\( x \)[/tex], which is always non-negative. That means [tex]\( |x| \geq 0 \)[/tex] for all [tex]\( x \)[/tex].
- Therefore, the minimum value of [tex]\( |x| \)[/tex] is [tex]\( 0 \)[/tex].
- Adding [tex]\( 3 \)[/tex] to [tex]\( |x| \)[/tex], we get the minimum value of [tex]\( |x| + 3 = 0 + 3 = 3 \)[/tex].

4. Range of [tex]\( (f + g)(x) \)[/tex]:
- Because [tex]\( |x| \geq 0 \)[/tex], the expression [tex]\( |x| + 3 \)[/tex] will always be greater than or equal to [tex]\( 3 \)[/tex].
- Hence, [tex]\( (f + g)(x) \geq 3 \)[/tex] for all values of [tex]\( x \)[/tex].

5. Conclusion:
The correct option that describes the range of [tex]\( (f + g)(x) \)[/tex] is:
[tex]\[ (f+g)(x) \geq 3 \text{ for all values of } x \][/tex]

So, the answer is that the range of [tex]\( (f+g)(x) \)[/tex] is given by:
[tex]\[ \boxed{(f+g)(x) \geq 3 \text{ for all values of } x} \][/tex]