Rewrite as equivalent rational expressions with denominator [tex](5c+9)(c-3)(c-8)[/tex]:

[tex]\frac{8}{5c^2 - 6c - 27}, \frac{2c}{5c^2 - 31c - 72}[/tex]



Answer :

Absolutely, I'll guide you through rewriting the given rational expressions with a common denominator step-by-step.

### Step 1: Factor the Denominators

First, we need to factor the denominators of the given fractions.

Given:
[tex]\[ \frac{8}{5c^2 - 6c - 27} \][/tex]
[tex]\[ \frac{2c}{5c^2 - 31c - 72} \][/tex]

To factor the quadratic denominators, we find the factors for each.

#### For [tex]\( 5c^2 - 6c - 27 \)[/tex]:

Factor the quadratic expression:
[tex]\[ 5c^2 - 6c - 27 = (5c + 9)(c - 3) \][/tex]

Verification:
Expanding [tex]\( (5c + 9)(c - 3) \)[/tex]:
[tex]\[ 5c \cdot c - 5c \cdot 3 + 9 \cdot c + 9 \cdot -3 = 5c^2 - 15c + 9c - 27 = 5c^2 - 6c - 27 \][/tex]

So, verified as correct.

#### For [tex]\( 5c^2 - 31c - 72 \)[/tex]:

Factor the quadratic expression:
[tex]\[ 5c^2 - 31c - 72 = (5c + 9)(c - 8) \][/tex]

Verification:
Expanding [tex]\( (5c + 9)(c - 8) \)[/tex]:
[tex]\[ 5c \cdot c - 5c \cdot 8 + 9 \cdot c + 9 \cdot -8 = 5c^2 - 40c + 9c - 72 = 5c^2 - 31c - 72 \][/tex]

Again, verified as correct.

### Step 2: Determine the Common Denominator

The common denominator for both fractions is:
[tex]\[ (5c+9)(c-3)(c-8) \][/tex]

### Step 3: Rewrite the Fractions with the Common Denominator

To rewrite each fraction with the common denominator, we will adjust the numerators accordingly.

#### For the first fraction:
[tex]\[ \frac{8}{5c^2 - 6c - 27} \][/tex]
Using the factorization:
[tex]\[ 5c^2 - 6c - 27 = (5c + 9)(c - 3) \][/tex]

To have the common denominator [tex]\((5c+9)(c-3)(c-8)\)[/tex], we multiply the numerator and denominator by [tex]\((c - 8)\)[/tex]:
[tex]\[ \frac{8}{(5c + 9)(c - 3)} \cdot \frac{(c - 8)}{(c - 8)} = \frac{8(c - 8)}{(5c + 9)(c - 3)(c - 8)} = \frac{8c - 64}{(5c + 9)(c - 3)(c - 8)} \][/tex]

#### For the second fraction:
[tex]\[ \frac{2c}{5c^2 - 31c - 72} \][/tex]
Using the factorization:
[tex]\[ 5c^2 - 31c - 72 = (5c + 9)(c - 8) \][/tex]

To have the common denominator [tex]\((5c+9)(c-3)(c-8)\)[/tex], we multiply the numerator and denominator by [tex]\((c - 3)\)[/tex]:
[tex]\[ \frac{2c}{(5c + 9)(c - 8)} \cdot \frac{(c - 3)}{(c - 3)} = \frac{2c(c - 3)}{(5c + 9)(c - 8)(c - 3)} = \frac{2c^2 - 6c}{(5c + 9)(c - 8)(c - 3)} \][/tex]

### Conclusion

The equivalent rational expressions with the common denominator [tex]\((5c+9)(c-3)(c-8)\)[/tex] are:

[tex]\[ \frac{8c - 64}{(5c + 9)(c - 3)(c - 8)} \][/tex]
[tex]\[ \frac{2c^2 - 6c}{(5c + 9)(c - 8)(c - 3)} \][/tex]

These are the rewritten forms of the given fractions with the common denominator.