Question

simplify - under root 45 - 3 under root 20 + 4 under root 5

Answer 1

This is the answer for your question

Answer 2

Step-by-step explanation:

$\bf \underline{Solution-}$

$\sf{ \sqrt{45} - 3 \sqrt{20} + 4 \sqrt{5} }$

$\sf{ = \sqrt{9 \times 5} - 3 \sqrt{4 \times 5} + 4 \sqrt{5} }$

$\sf{ = 3 \sqrt{5} - 3 \times 2 \sqrt{5} + 4 \sqrt{5} }$

$\sf{ = (3 - 6 + 4) \sqrt{5} }$

$\sf{ = \sqrt{5} } \: \: \: \: \bf{Ans.}$