1. **State the problem:** Simplify the expression $$\frac{x^2 - 25}{x^2 + 5x} \div \frac{xy + 6x - 5y - 30}{5x - 15}$$.
2. **Rewrite division as multiplication by reciprocal:**
$$\frac{x^2 - 25}{x^2 + 5x} \times \frac{5x - 15}{xy + 6x - 5y - 30}$$
3. **Factor all polynomials:**
- $x^2 - 25 = (x - 5)(x + 5)$ (difference of squares)
- $x^2 + 5x = x(x + 5)$
- $5x - 15 = 5(x - 3)$
- Factor $xy + 6x - 5y - 30$ by grouping:
$$xy + 6x - 5y - 30 = x(y + 6) - 5(y + 6) = (x - 5)(y + 6)$$
4. **Substitute factored forms:**
$$\frac{(x - 5)(x + 5)}{x(x + 5)} \times \frac{5(x - 3)}{(x - 5)(y + 6)}$$
5. **Cancel common factors:**
- Cancel $(x + 5)$ in numerator and denominator
- Cancel $(x - 5)$ in numerator and denominator
Intermediate step showing cancellation:
$$\frac{\cancel{(x - 5)}\cancel{(x + 5)}}{x\cancel{(x + 5)}} \times \frac{5(x - 3)}{\cancel{(x - 5)}(y + 6)} = \frac{1}{x} \times \frac{5(x - 3)}{y + 6}$$
6. **Multiply remaining factors:**
$$\frac{1}{x} \times \frac{5(x - 3)}{y + 6} = \frac{5(x - 3)}{x(y + 6)}$$
**Final answer:**
$$\boxed{\frac{5(x - 3)}{x(y + 6)}}$$
Rational Expression Division Be62A5
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