Solve. $LaTeX: \displaystyle \sqrt{x + 18}=\sqrt{x - 8} + 4$

Squaring both sides gives $LaTeX: \displaystyle x + 18=x + 8 \sqrt{x - 8} + 8$ . Isolating the radical gives $LaTeX: \displaystyle \frac{5}{4}=\sqrt{x - 8}$ Squaring again gives $LaTeX: \displaystyle \frac{25}{16}=x - 8$ . Solving for $LaTeX: \displaystyle x$ gives $LaTeX: \displaystyle x=\frac{153}{16}$ . Checking the solution, $LaTeX: \displaystyle x = \frac{153}{16}$ , in the original equation gives $LaTeX: \displaystyle \frac{21}{4} = \frac{21}{4}$ which is true so the solution checks.