Solve. LaTeX:  \displaystyle \sqrt{x + 22}=\sqrt{x - 4} - 4

Squaring both sides gives LaTeX:  \displaystyle x + 22=x - 8 \sqrt{x - 4} + 12 . Isolating the radical gives LaTeX:  \displaystyle - \frac{5}{4}=\sqrt{x - 4} Squaring again gives LaTeX:  \displaystyle \frac{25}{16}=x - 4 . Solving for LaTeX:  \displaystyle x gives LaTeX:  \displaystyle x=\frac{89}{16} . Checking the solution, LaTeX:  \displaystyle x = \frac{89}{16} , in the original equation gives LaTeX:  \displaystyle \frac{21}{4} = - \frac{11}{4} which is false so it is an extraneous solution and there is no solution.