1. **State the problem:** Simplify the expression $$74 \cdot (3x+2)(3x-9) + (5x^2 - 7x^3)$$.
2. **Recall the distributive property and FOIL method:** To multiply two binomials, use FOIL (First, Outer, Inner, Last).
3. **Multiply the binomials:**
$$(3x+2)(3x-9) = 3x \cdot 3x + 3x \cdot (-9) + 2 \cdot 3x + 2 \cdot (-9)$$
$$= 9x^2 - 27x + 6x - 18$$
$$= 9x^2 - 21x - 18$$
4. **Multiply the result by 74:**
$$74 \cdot (9x^2 - 21x - 18) = 74 \cdot 9x^2 - 74 \cdot 21x - 74 \cdot 18$$
$$= 666x^2 - 1554x - 1332$$
5. **Add the remaining polynomial:**
$$666x^2 - 1554x - 1332 + 5x^2 - 7x^3$$
6. **Combine like terms:**
$$-7x^3 + (666x^2 + 5x^2) - 1554x - 1332$$
$$= -7x^3 + 671x^2 - 1554x - 1332$$
**Final answer:**
$$\boxed{-7x^3 + 671x^2 - 1554x - 1332}$$
Simplify Polynomial D3732D
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