1. **State the problem:** Simplify the expression $$\frac{2m^2 + 9m - 5}{3m^2 + 13m - 10} \div \frac{14m - 7}{4 - 9m^2}$$.
2. **Recall the division of fractions rule:** Dividing by a fraction is the same as multiplying by its reciprocal.
3. **Rewrite the division as multiplication:**
$$\frac{2m^2 + 9m - 5}{3m^2 + 13m - 10} \times \frac{4 - 9m^2}{14m - 7}$$
4. **Factor all polynomials where possible:**
- Numerator 1: $2m^2 + 9m - 5 = (2m - 1)(m + 5)$
- Denominator 1: $3m^2 + 13m - 10 = (3m - 2)(m + 5)$
- Numerator 2: $4 - 9m^2 = (2 - 3m)(2 + 3m)$ (difference of squares)
- Denominator 2: $14m - 7 = 7(2m - 1)$
5. **Substitute the factored forms:**
$$\frac{(2m - 1)(m + 5)}{(3m - 2)(m + 5)} \times \frac{(2 - 3m)(2 + 3m)}{7(2m - 1)}$$
6. **Cancel common factors:**
- Cancel $(m + 5)$ from numerator and denominator.
- Cancel $(2m - 1)$ from numerator and denominator.
Intermediate step showing cancellation:
$$\frac{\cancel{(2m - 1)}\cancel{(m + 5)}}{(3m - 2)\cancel{(m + 5)}} \times \frac{(2 - 3m)(2 + 3m)}{7\cancel{(2m - 1)}}$$
7. **Simplify the expression:**
$$\frac{1}{3m - 2} \times \frac{(2 - 3m)(2 + 3m)}{7} = \frac{(2 - 3m)(2 + 3m)}{7(3m - 2)}$$
8. **Note that $2 - 3m = -(3m - 2)$, so:**
$$\frac{-(3m - 2)(2 + 3m)}{7(3m - 2)}$$
9. **Cancel $(3m - 2)$ terms:**
$$\frac{\cancel{-(3m - 2)}(2 + 3m)}{7\cancel{(3m - 2)}} = \frac{-(2 + 3m)}{7} = \frac{-2 - 3m}{7}$$
**Final answer:**
$$\boxed{\frac{-2 - 3m}{7}}$$
Fraction Division Ed4Daf
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