Answer :

Sure, let's go through these questions step-by-step.

### 7. Write five rational numbers equivalent to [tex]\(\frac{5}{-11}\)[/tex].

To find equivalent fractions, you can multiply the numerator and the denominator of the fraction by the same non-zero integer.

Given fraction: [tex]\(\frac{5}{-11}\)[/tex]

1. Multiply by [tex]\(1\)[/tex]:
[tex]\[ \frac{5 \times 1}{-11 \times 1} = \frac{5}{-11} \][/tex]

2. Multiply by [tex]\(-1\)[/tex]:
[tex]\[ \frac{5 \times -1}{-11 \times -1} = \frac{-5}{11} \][/tex]

3. Multiply by [tex]\(2\)[/tex]:
[tex]\[ \frac{5 \times 2}{-11 \times 2} = \frac{10}{-22} \][/tex]

4. Multiply by [tex]\(-2\)[/tex]:
[tex]\[ \frac{5 \times -2}{-11 \times -2} = \frac{-10}{22} \][/tex]

5. Multiply by [tex]\(3\)[/tex]:
[tex]\[ \frac{5 \times 3}{-11 \times 3} = \frac{15}{-33} \][/tex]

Thus, five rational numbers equivalent to [tex]\(\frac{5}{-11}\)[/tex] are:

[tex]\[ \frac{5}{-11}, \quad \frac{-5}{11}, \quad \frac{10}{-22}, \quad \frac{-10}{22}, \quad \frac{15}{-33} \][/tex]

### 8. Show that [tex]\(\frac{-18}{18}\)[/tex] and [tex]\(\frac{-3}{3}\)[/tex] are equivalent rational numbers.

First, simplify the fractions:

[tex]\(\frac{-18}{18}\)[/tex]:
[tex]\[ -18 \div 18 = -1 \][/tex]
So,
[tex]\[ \frac{-18}{18} = -1 \][/tex]

[tex]\(\frac{-3}{3}\)[/tex]:
[tex]\[ -3 \div 3 = -1 \][/tex]
So,
[tex]\[ \frac{-3}{3} = -1 \][/tex]

Since both [tex]\(\frac{-18}{18}\)[/tex] and [tex]\(\frac{-3}{3}\)[/tex] simplify to [tex]\(-1\)[/tex], we can conclude that:

[tex]\[ \frac{-18}{18} = \frac{-3}{3} \][/tex]

Thus, [tex]\(\frac{-18}{18}\)[/tex] and [tex]\(\frac{-3}{3}\)[/tex] are equivalent rational numbers.