Solve the inequality [tex]\frac{r}{-2.5} \leq 8.7[/tex] for [tex]r[/tex].

A. [tex]r \geq -3.48[/tex]
B. [tex]r \leq 3.48[/tex]
C. [tex]r \geq -21.75[/tex]
D. [tex]r \leq -21.75[/tex]



Answer :

To solve the inequality [tex]\(\frac{r}{-2.5} \leq 8.7\)[/tex] for [tex]\(r\)[/tex], follow these steps:

1. Recognize that you need to isolate the variable [tex]\(r\)[/tex]. The current form of the inequality involves [tex]\(r\)[/tex] being divided by [tex]\(-2.5\)[/tex]. To isolate [tex]\(r\)[/tex], you need to eliminate the division by [tex]\(-2.5\)[/tex].

2. To eliminate the division, multiply both sides of the inequality by [tex]\(-2.5\)[/tex]. Remember, when you multiply or divide both sides of an inequality by a negative number, you must reverse the direction of the inequality sign:
[tex]\[ \left(\frac{r}{-2.5}\right) \cdot (-2.5) \geq 8.7 \cdot (-2.5) \][/tex]

3. Simplify both sides:
[tex]\[ r \geq 8.7 \cdot (-2.5) \][/tex]

4. Calculate the product on the right side:
[tex]\[ 8.7 \cdot (-2.5) = -21.75 \][/tex]

5. Rewrite the inequality with the calculated value:
[tex]\[ r \geq -21.75 \][/tex]

Thus, the solution to the inequality [tex]\(\frac{r}{-2.5} \leq 8.7\)[/tex] is [tex]\(r \geq -21.75\)[/tex].

The correct answer is [tex]\(r \geq -21.75\)[/tex].