Question

Simplify square root 24 minus 3 times the square root of 45 plus 2 times the square root of 20

a 7 minus 3 times square root 30
b 2 square root 6 minus 5 square root 5
c 2 square root 6 minus 2 square root 5
d 4 square root 6 minus 19 square root 5

Answer 1

`√(24)-3 √(45)+2 √(20)=√(6 \cdot 4)- 3 √(9 \cdot 5)+2 √(5 \cdot 4)=2\sqrt 6-3 \cdot 3 \sqrt 5+`

`+2 \cdot 2 \sqrt 5 = 2\sqrt 6 - 9 \sqrt 5 + 4 \sqrt 5 = \boxed{2 \sqrt 6 - 5 \sqrt 5} - Option B`