College

Solve for [tex]x[/tex] in the equation [tex]5|x+9|=80[/tex].

A. [tex]x = 7[/tex] or [tex]x = 16[/tex]
B. [tex]x = -7[/tex] or [tex]x = 25[/tex]
C. [tex]x = -25[/tex] or [tex]x = 9[/tex]
D. [tex]x = -25[/tex] or [tex]x = 7[/tex]

Answer :

Certainly! Let's solve the equation [tex]\(5|x+9|=80\)[/tex] step by step.

1. Divide both sides by 5:

Start with the equation:
[tex]\[
5|x + 9| = 80
\][/tex]
Divide both sides by 5 to isolate the absolute value:
[tex]\[
|x + 9| = \frac{80}{5} = 16
\][/tex]

2. Set up two separate equations:

The absolute value equation [tex]\( |x + 9| = 16 \)[/tex] gives us two possible equations:
- [tex]\( x + 9 = 16 \)[/tex]
- [tex]\( x + 9 = -16 \)[/tex]

3. Solve each equation for [tex]\( x \)[/tex]:

- For the first equation [tex]\( x + 9 = 16 \)[/tex]:
[tex]\[
x = 16 - 9 = 7
\][/tex]

- For the second equation [tex]\( x + 9 = -16 \)[/tex]:
[tex]\[
x = -16 - 9 = -25
\][/tex]

4. Conclusion:

The solutions to the equation [tex]\( 5|x+9|=80 \)[/tex] are [tex]\( x = 7 \)[/tex] and [tex]\( x = -25 \)[/tex].

Therefore, the correct answer is [tex]\( x = -25 \)[/tex] or [tex]\( x = 7 \)[/tex], which corresponds to option D.