1. **Problem:** Solve the equation $3^x 5^{x-1} = 6^{x+2}$.
2. **Rewrite the equation:**
$$3^x 5^{x-1} = 6^{x+2}$$
Rewrite $5^{x-1}$ as $5^x / 5$ and $6^{x+2}$ as $6^x \times 6^2$:
$$3^x \times \frac{5^x}{5} = 6^x \times 36$$
3. **Combine terms:**
$$\frac{3^x 5^x}{5} = 36 \times 6^x$$
$$\frac{(3 \times 5)^x}{5} = 36 \times 6^x$$
$$\frac{15^x}{5} = 36 \times 6^x$$
4. **Divide both sides by $6^x$:**
$$\frac{15^x}{5 \times 6^x} = 36$$
$$\frac{15^x}{6^x} \times \frac{1}{5} = 36$$
$$\frac{(15/6)^x}{5} = 36$$
5. **Multiply both sides by 5:**
$$\cancel{\frac{(15/6)^x}{\cancel{5}}} \times 5 = 36 \times 5$$
$$(15/6)^x = 180$$
6. **Take natural logarithm of both sides:**
$$x \ln\left(\frac{15}{6}\right) = \ln 180$$
7. **Solve for $x$:**
$$x = \frac{\ln 180}{\ln \frac{15}{6}} \approx \frac{5.19296}{0.91629} \approx 5.666$$
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**Note:** The user’s intermediate value $x = 2.1544$ seems to be from a different step or calculation; the correct solution here is approximately $5.666$.
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**Slug:** exponential equation
**Subject:** algebra
**Desmos:** {"latex":"y=(15/6)^x - 180","features":{"intercepts":true,"extrema":true}}
**q_count:** 1
Exponential Equation 8E3F08
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