Answer
{$\frac{\log 20}{\log 7}$}, {$1.5395$}
Work Step by Step
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 {$1.5395$}.
