Question

Simplify
$\sqrt{45}+\sqrt{20}-\sqrt5$

• A. 4√5
• B. 6√5
• C. 5√5
• D. 3√5

Answer 1

Answer:

A. 4√5

$\sqrt{45}+\sqrt{20}-\sqrt5$

Simplify each radical:

$\sqrt{45}=\sqrt{9\times5}=3\sqrt5$
$\sqrt{20}=\sqrt{4\times5}=2\sqrt5$

Therefore,

$3\sqrt5+2\sqrt5-\sqrt5$
$=(3+2-1)\sqrt5$
$\boxed{4\sqrt5}$