[tex] \sqrt{x + 8} + \sqrt{x} = 4 \\ \sqrt{x + 8} = 4 - \sqrt{x} \\ x + 8 = 16 - 8 \sqrt{x} + x \\ 8 = 16 - 8 \sqrt{x} \\ 8 \sqrt{x} = 16 - 8 \\ 8 \sqrt{x} = 8 \\ \\ \sqrt{x} = \frac{8}{8} \\ \\ \sqrt{x} = 1 \\ \\ x = 1.[/tex]
