1. **State the problem:** Solve the equation $$9^{3x - 7} = 81^{x + 2}$$.
2. **Rewrite bases as powers of the same base:**
Since $$9 = 3^2$$ and $$81 = 3^4$$, rewrite the equation as:
$$ (3^2)^{3x - 7} = (3^4)^{x + 2} $$
3. **Apply power of a power rule:**
$$ 3^{2(3x - 7)} = 3^{4(x + 2)} $$
4. **Simplify exponents:**
$$ 3^{6x - 14} = 3^{4x + 8} $$
5. **Since the bases are equal, set exponents equal:**
$$ 6x - 14 = 4x + 8 $$
6. **Solve for $$x$$:**
$$ 6x - 4x = 8 + 14 $$
$$ 2x = 22 $$
$$ x = \frac{22}{2} $$
$$ x = 11 $$
7. **Final answer:**
The solution set is $$\{11\}$$.
Exponential Equation 90305C
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