1. **State the problem:** Solve the equation $2^{x+2} - 2^{x+5} = -7$ for $x$.
2. **Recall the properties of exponents:**
- $a^{m+n} = a^m \cdot a^n$
- We can factor expressions with common bases.
3. **Rewrite the terms:**
$$2^{x+2} = 2^x \cdot 2^2 = 4 \cdot 2^x$$
$$2^{x+5} = 2^x \cdot 2^5 = 32 \cdot 2^x$$
4. **Substitute back into the equation:**
$$4 \cdot 2^x - 32 \cdot 2^x = -7$$
5. **Factor out $2^x$:**
$$2^x (4 - 32) = -7$$
$$2^x \cancel{(4 - 32)} = -7$$
$$2^x (-28) = -7$$
6. **Divide both sides by $-28$:**
$$2^x = \frac{-7}{-28} = \frac{7}{28}$$
$$2^x = \frac{1}{4}$$
7. **Rewrite $\frac{1}{4}$ as a power of 2:**
$$\frac{1}{4} = 2^{-2}$$
8. **Set the exponents equal:**
$$x = -2$$
**Final answer:**
$$x = -2$$
Exponential Equation 209Bce
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