Chapter 7 Exponential and Logarithmic Functions - 7.6 Solve Exponential and Logarithmic Equations - 7.6 Exercises - Skill Practice - Page 520: 34

$$x=\frac{15625}{12}$$

Using the rules of logarithms to solve the equation, we find: $$\log _5\left(12x\right)=6 \\ \log _5\left(12x\right)=\log _5\left(15625\right) \\ 12x=15625 \\ x=\frac{15625}{12}$$ Checking for extraneous solutions, we see that the given solution is valid.