Question

Simplify 2√45-5√20+√80

Answer 1

$\sf{ \looparrowright 2 \sqrt{45} - 5 \sqrt{20} + \sqrt{80}} \\ \tt{( \sqrt{45} = 3 \sqrt{5}, \sqrt{20} = 2 \sqrt{5}, \sqrt{80} = 4 \sqrt{5} )}$

$\sf{ \looparrowright2(3 \sqrt{5}) - 5(2 \sqrt{5} ) + 4 \sqrt{5} } \\ \sf{ \looparrowright6 \sqrt{5} - 10 \sqrt{5} + 4 \sqrt{5} } \\ \sf \pink{ \looparrowright10 \sqrt{5} - 10 \sqrt{5} = 0 }$