## Algebra: A Combined Approach (4th Edition)

{$\frac{\log 20}{\log 7}$}, {$1.5395$}
Step 1: $7^{x}=20$ Step 2: $\log 7^{x}=\log 20$ Step 3: $x\log 7=\log 20$ Step 4: $x=\frac{\log 20}{\log 7}\approx1.5395$ Therefore, the exact solution is {$\frac{\log 20}{\log 7}$} whereas the four decimal approximation is {$1.5395$}.