Question

Simplify-6√20+2√45+7√5 show Woking out to prove ans please​

Answer 1

Answer:

$\sqrt{5}$

Step-by-step explanation:

Using the rule of radicals

$\sqrt{a}$ × $\sqrt{b}$ ⇔ $\sqrt{ab}$

Simplifying the radicals

$\sqrt{20}$ = $\sqrt{4(5)}$ = $\sqrt{4}$ × $\sqrt{5}$ = 2$\sqrt{5}$

$\sqrt{45}$ = $\sqrt{9(5)}$ = $\sqrt{9}$ × $\sqrt{5}$ = 3$\sqrt{5}$

Thus

- 6(2$\sqrt{5}$) + 2(3$\sqrt{5}$) + 7$\sqrt{5}$

= - 12$\sqrt{5}$ + 6$\sqrt{5}$ + 7$\sqrt{5}$

= $\sqrt{5}$