Solve LaTeX:  \displaystyle \log_{ 3 }(x + 6) + \log_{ 3 }(x + 6) = 2

Using the product rule for logarithms gives LaTeX:  \displaystyle \log_{ 3 }(\left(x + 6\right)^{2})  and rewriting in exponential form gives LaTeX:  \displaystyle \left(x + 6\right)^{2} = 9 expanding and setting the equation equal to zero gives LaTeX:  \displaystyle x^{2} + 12 x + 27 = 0 . Factoring gives LaTeX:  \displaystyle \left(x + 3\right) \left(x + 9\right)=0 . This gives two possible solutions LaTeX:  \displaystyle x=-9 or LaTeX:  \displaystyle x=-3 . LaTeX:  \displaystyle x=-9 is an extraneous solution. The only soution is LaTeX:  \displaystyle x=-3 .