Answer:
8√2
Step-by-step explanation:
Simplify √18 which is 3√2
5√2+3√2=8√2
[tex]\large\boxed{5\sqrt2+\sqrt{18}=8\sqrt2}[/tex]
[tex]5\sqrt2+\sqrt{18}=5\sqrt2+\sqrt{9\cdot2}\\\\\text{use}\ \sqrt{ab}=\sqrt{a}\cdot\sqrt{b}\\\\=5\sqrt2+\sqrt9\cdot\sqrt2=5\sqrt2+3\sqrt2=(5+3)\sqrt2=8\sqrt2[/tex]
