Question

9. Simplify the following:
√45-3√20+4√5​

Answer 1

Answer:

$\sqrt{5}$

Step-by-step explanation:

$\sqrt{45 } - 3 \sqrt{20} + 4 \sqrt{5 } \\ \\ = \sqrt{5 } 3 \sqrt{5 } - 6 \sqrt{5} + 4 \sqrt{5} \\ \\ = 7 \sqrt{5} - 6 \sqrt{5} \\ = \sqrt{5}$

Answer 2

Step-by-step explanation:

$\bf \underline{Solution-}$

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

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

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

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

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