Question

Evaluate 5√2 + √18

Answer 1

Answer:

8$\sqrt{2}$

Step-by-step explanation:

Using the rule of radicals

• $\sqrt{a}$ × $\sqrt{b}$ ⇔ $\sqrt{ab}$, then

$\sqrt{18}$

= $\sqrt{9(2)}$ = $\sqrt{9}$ × $\sqrt{2}$ = 3$\sqrt{2}$

Hence

5$\sqrt{2}$ + 3$\sqrt{2}$ = 8$\sqrt{2}$ ≈ 11.31

Answer 2

Answer:

$\large\boxed{5\sqrt2+\sqrt{18}=8\sqrt2}$

Step-by-step explanation:

$5\sqrt2+\sqrt{18}=5\sqrt2+\sqrt{9\cdot2}\\\\\text{use}\ \sqrt{ab}=\sqrt{a}\cdot\sqrt{b}\\\\=5\sqrt2+\sqrt9\cdot\sqrt2=5\sqrt2+3\sqrt2=(5+3)\sqrt2=8\sqrt2$