Solve. LaTeX:  \displaystyle \sqrt{x + 20}=\sqrt{x + 6} - 2

Squaring both sides gives LaTeX:  \displaystyle x + 20=x - 4 \sqrt{x + 6} + 10 . Isolating the radical gives LaTeX:  \displaystyle - \frac{5}{2}=\sqrt{x + 6} Squaring again gives LaTeX:  \displaystyle \frac{25}{4}=x + 6 . Solving for LaTeX:  \displaystyle x gives LaTeX:  \displaystyle x=\frac{1}{4} . Checking the solution, LaTeX:  \displaystyle x = \frac{1}{4} , in the original equation gives LaTeX:  \displaystyle \frac{9}{2} = \frac{1}{2} which is false so it is an extraneous solution and there is no solution.