Which of the following is the solution to [tex]$3|x-1| \geq 12$[/tex]?

A. [tex]x \geq -3[/tex] or [tex]x \geq 5[/tex]

B. [tex]x \leq -3[/tex] or [tex]x \geq 5[/tex]

C. [tex]x \leq -3[/tex] and [tex]x \geq 5[/tex]

D. [tex]x \geq 5[/tex]



Answer :

To solve the inequality [tex]\(3|x-1| \geq 12\)[/tex], let’s go through the steps methodically.

1. Isolate the absolute value expression:
[tex]\[ 3|x-1| \geq 12 \][/tex]
Divide both sides by 3 to simplify:
[tex]\[ |x-1| \geq 4 \][/tex]

2. Break the absolute value inequality into two separate inequalities:
The absolute value expression [tex]\( |x-1| \geq 4 \)[/tex] implies two cases:
[tex]\[ x-1 \geq 4 \quad \text{or} \quad x-1 \leq -4 \][/tex]

3. Solve each inequality separately:

- For the first inequality [tex]\( x-1 \geq 4 \)[/tex]:
[tex]\[ x \geq 4 + 1 \][/tex]
[tex]\[ x \geq 5 \][/tex]

- For the second inequality [tex]\( x-1 \leq -4 \)[/tex]:
[tex]\[ x \leq -4 + 1 \][/tex]
[tex]\[ x \leq -3 \][/tex]

4. Combine the solutions:
The solutions from the two inequalities are [tex]\( x \geq 5 \)[/tex] or [tex]\( x \leq -3 \)[/tex].

Therefore, the solution to the inequality [tex]\(3|x-1| \geq 12\)[/tex] is:

[tex]\[ x \leq -3 \quad \text{or} \quad x \geq 5 \][/tex]

This corresponds to option B in the given choices.

Final Answer: B. [tex]\( x \leq -3 \)[/tex] or [tex]\( x \geq 5 \)[/tex].