Which compound inequality does the number line represent?

A. [tex]5x \geq -15[/tex] or [tex]5x \ \textless \ 10[/tex]

B. [tex]2x \leq -6[/tex] or [tex]2x \geq 4[/tex]

C. [tex]-13 \leq 4x - 1 \ \textless \ 7[/tex]

D. [tex]-4x \geq 12[/tex] and [tex]-4x \ \textless \ -8[/tex]



Answer :

To determine which compound inequality the number line represents, we need to analyze each of the provided inequalities step by step.

1. Inequality: [tex]\(5x \geq -15\)[/tex] or [tex]\(5x < 10\)[/tex]

- To solve [tex]\(5x \geq -15\)[/tex]:
[tex]\[ x \geq \frac{-15}{5} \quad \Rightarrow \quad x \geq -3 \][/tex]

- To solve [tex]\(5x < 10\)[/tex]:
[tex]\[ x < \frac{10}{5} \quad \Rightarrow \quad x < 2 \][/tex]

So, the combined inequality is:
[tex]\[ x \geq -3 \quad \text{or} \quad x < 2 \][/tex]

2. Inequality: [tex]\(2x \leq -6\)[/tex] or [tex]\(2x \geq 4\)[/tex]

- To solve [tex]\(2x \leq -6\)[/tex]:
[tex]\[ x \leq \frac{-6}{2} \quad \Rightarrow \quad x \leq -3 \][/tex]

- To solve [tex]\(2x \geq 4\)[/tex]:
[tex]\[ x \geq \frac{4}{2} \quad \Rightarrow \quad x \geq 2 \][/tex]

So, the combined inequality is:
[tex]\[ x \leq -3 \quad \text{or} \quad x \geq 2 \][/tex]

3. Inequality: [tex]\(-13 \leq 4x - 1 < 7\)[/tex]

- To isolate [tex]\(x\)[/tex], first add 1 to all parts:
[tex]\[ -13 + 1 \leq 4x - 1 + 1 < 7 + 1 \quad \Rightarrow \quad -12 \leq 4x < 8 \][/tex]

- Next, divide all parts by 4:
[tex]\[ \frac{-12}{4} \leq \frac{4x}{4} < \frac{8}{4} \quad \Rightarrow \quad -3 \leq x < 2 \][/tex]

So, the inequality simplifies to:
[tex]\[ -3 \leq x < 2 \][/tex]

4. Inequality: [tex]\(-4x \geq 12\)[/tex] and [tex]\(-4x < -8\)[/tex]

- To solve [tex]\(-4x \geq 12\)[/tex]:
[tex]\[ x \leq \frac{12}{-4} \quad \Rightarrow \quad x \leq -3 \quad \text{(flip the inequality sign)} \][/tex]

- To solve [tex]\(-4x < -8\)[/tex]:
[tex]\[ x > \frac{-8}{-4} \quad \Rightarrow \quad x > 2 \quad \text{(flip the inequality sign)} \][/tex]

So, the combined inequality is:
[tex]\[ x \leq -3 \quad \text{and} \quad x > 2 \][/tex]

After evaluating each of these inequalities, we see that the inequality that matches a proper range on the number line is:

[tex]\[ -3 \leq x < 2 \][/tex]

Therefore, the combined inequality that the number line represents is:

[tex]\[ -13 \leq 4x - 1 < 7 \][/tex]

Thus, the answer is [tex]\(3\)[/tex].