SOLUTION: Can you please answer this problem? (3 times the square root of 20)-(7 times the square root of 45)

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Question 190509: Can you please answer this problem? (3 times the square root of 20)-(7 times the square root of 45)
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
Can you please answer this problem? (3 times the square root of 20)-(7 times the square root of 45)
3sqrt%2820%29+-+7sqrt%2845%29
sqrt(20) = sqrt(4)*sqrt(5) = 2sqrt(5)
sqrt(45) = sqrt(9)*sqrt(5) = 3sqrt(5)
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3sqrt%2820%29+-+7sqrt%2845%29
= 6sqrt%285%29+-+21sqrt%285%29
= -15sqrt%285%29