Question

subtract. write your answer in simples
$5\sqrt{18} - \sqrt{8}$

Explanation:

Step1: Simplify each square root

Simplify $\sqrt{18}$: $\sqrt{18}=\sqrt{9\times2}=3\sqrt{2}$ (since $\sqrt{9}=3$). Then $5\sqrt{18}=5\times3\sqrt{2}=15\sqrt{2}$.
Simplify $\sqrt{8}$: $\sqrt{8}=\sqrt{4\times2}=2\sqrt{2}$ (since $\sqrt{4}=2$).

Step2: Subtract the simplified radicals

Now subtract the two terms: $15\sqrt{2}-2\sqrt{2}$.
Since the radicals are the same, we combine the coefficients: $(15 - 2)\sqrt{2}=13\sqrt{2}$.

Answer:

$13\sqrt{2}$