1. **State the problem:** Simplify the expression $$\frac{x^2 - 25}{x^2 + 5x} \div \frac{xy + 6x - 5y - 30}{5x - 15}$$.
2. **Recall the division rule for fractions:** Dividing by a fraction is the same as multiplying by its reciprocal:
$$\frac{a}{b} \div \frac{c}{d} = \frac{a}{b} \times \frac{d}{c}$$.
3. **Apply the rule:**
$$\frac{x^2 - 25}{x^2 + 5x} \times \frac{5x - 15}{xy + 6x - 5y - 30}$$.
4. **Factor all polynomials:**
- Numerator 1: $$x^2 - 25 = (x - 5)(x + 5)$$ (difference of squares).
- Denominator 1: $$x^2 + 5x = x(x + 5)$$ (factor out common x).
- Numerator 2: $$5x - 15 = 5(x - 3)$$ (factor out 5).
- Denominator 2: $$xy + 6x - 5y - 30$$ group terms:
$$x(y + 6) - 5(y + 6) = (x - 5)(y + 6)$$.
5. **Rewrite the expression with factors:**
$$\frac{(x - 5)(x + 5)}{x(x + 5)} \times \frac{5(x - 3)}{(x - 5)(y + 6)}$$.
6. **Multiply the fractions:**
$$\frac{(x - 5)(x + 5) \times 5(x - 3)}{x(x + 5)(x - 5)(y + 6)}$$.
7. **Cancel common factors:**
- Cancel $(x - 5)$ numerator and denominator.
- Cancel $(x + 5)$ numerator and denominator.
Intermediate step with cancellation:
$$\frac{\cancel{(x - 5)} \cancel{(x + 5)} \times 5(x - 3)}{x \cancel{(x + 5)} \cancel{(x - 5)} (y + 6)} = \frac{5(x - 3)}{x(y + 6)}$$.
8. **Final simplified expression:**
$$\boxed{\frac{5(x - 3)}{x(y + 6)}}$$.
This is the simplified form of the original expression.
Fraction Division 831F3F
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