Solve Exponential 6A25C0
1. **State the problem:** Solve the equation $$7^x = 3^x + 4$$ for $x$.
2. **Understand the equation:** We want to find the value of $x$ such that the exponential expression on the left equals the sum on the right.
3. **Rewrite the equation:**
$$7^x - 3^x = 4$$
4. **Consider the behavior of the function:** Define $$f(x) = 7^x - 3^x - 4$$. We want to find $x$ such that $f(x) = 0$.
5. **Check integer values:**
- For $x=1$: $$7^1 - 3^1 - 4 = 7 - 3 - 4 = 0$$
6. **Conclusion:** Since $f(1) = 0$, $x=1$ is a solution.
7. **Check if there are other solutions:**
- For $x=0$: $$7^0 - 3^0 - 4 = 1 - 1 - 4 = -4 < 0$$
- For $x=2$: $$7^2 - 3^2 - 4 = 49 - 9 - 4 = 36 > 0$$
Since $f(x)$ is continuous and increasing (because $7^x$ grows faster than $3^x$), and it crosses zero at $x=1$, this is the unique solution.
**Final answer:** $$x = 1$$