<PRE><B>Question 190509</B>
Can you please answer this problem? (3 times the square root of 20)-(7 times the square root of 45)
{{{3sqrt(20) - 7sqrt(45)}}}
sqrt(20) = sqrt(4)*sqrt(5) = 2sqrt(5)
sqrt(45) = sqrt(9)*sqrt(5) = 3sqrt(5)
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{{{3sqrt(20) - 7sqrt(45)}}}
= {{{6sqrt(5) - 21sqrt(5)}}}
= {{{-15sqrt(5)}}}

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