Solve. LaTeX:  \displaystyle \sqrt{x + 16}=\sqrt{x - 4} - 3

Squaring both sides gives LaTeX:  \displaystyle x + 16=x - 6 \sqrt{x - 4} + 5 . Isolating the radical gives LaTeX:  \displaystyle - \frac{11}{6}=\sqrt{x - 4} Squaring again gives LaTeX:  \displaystyle \frac{121}{36}=x - 4 . Solving for LaTeX:  \displaystyle x gives LaTeX:  \displaystyle x=\frac{265}{36} . Checking the solution, LaTeX:  \displaystyle x = \frac{265}{36} , in the original equation gives LaTeX:  \displaystyle \frac{29}{6} = - \frac{7}{6} which is false so it is an extraneous solution and there is no solution.