Exponential Equation Df65B0
1. **State the problem:** Solve the equation $$2^{x+7} - 2^{x+6} = 1$$ for $x$.
2. **Recall the properties of exponents:**
- $a^{m+n} = a^m \cdot a^n$
- We can factor expressions with common bases and exponents.
3. **Rewrite the terms:**
$$2^{x+7} = 2^x \cdot 2^7 = 2^x \cdot 128$$
$$2^{x+6} = 2^x \cdot 2^6 = 2^x \cdot 64$$
4. **Substitute back into the equation:**
$$2^x \cdot 128 - 2^x \cdot 64 = 1$$
5. **Factor out $2^x$:**
$$2^x (128 - 64) = 1$$
$$2^x \cdot 64 = 1$$
6. **Divide both sides by 64:**
$$2^x = \frac{1}{64}$$
7. **Express $\frac{1}{64}$ as a power of 2:**
Since $64 = 2^6$, then
$$\frac{1}{64} = 2^{-6}$$
8. **Set the exponents equal:**
$$2^x = 2^{-6} \implies x = -6$$
**Final answer:**
$$x = -6$$