1. **State the problem:** Solve the equation $$e^{x+1} - 18e^x - 3 = 0$$ for $x$.
2. **Rewrite the equation:** Use the property of exponents: $$e^{x+1} = e^x \cdot e^1 = e \cdot e^x$$.
3. **Substitute:** Let $$y = e^x$$, then the equation becomes:
$$e \cdot y - 18y - 3 = 0$$
4. **Factor the equation:**
$$y(e - 18) - 3 = 0$$
5. **Isolate $y$:**
$$y(e - 18) = 3$$
$$y = \frac{3}{e - 18}$$
6. **Recall substitution:**
$$e^x = \frac{3}{e - 18}$$
7. **Solve for $x$:** Take the natural logarithm on both sides:
$$x = \ln\left(\frac{3}{e - 18}\right)$$
8. **Check domain:** Since $e \approx 2.718$, $e - 18 < 0$, so denominator is negative, making the fraction negative. $e^x$ is always positive, so no real solution exists.
**Final answer:** No real solution for $x$.
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**Slug:** exponential equation
**Subject:** algebra
**Desmos:** {"latex":"e^{x+1} - 18e^x - 3 = 0","features":{"intercepts":true,"extrema":true}}
**q_count:** 3
Exponential Equation 788Dcd
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