$2 \log_{10} 3 + \log_{10} 5 - \log_{10} 9 = \log_{10} ?$

Combining gives $\log_{10}\dfrac{3^2\times5}{9} = \log_{10}\dfrac{45}{9} = \log_{10}5$, since $2\log_{10}3 = \log_{10}9$ cancels the $-\log_{10}9$.