How do you simplify $-5sqrt21*-3sqrt42$ ?

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Answer 1 · 2015-04-10T11:40:49

You can write your product as:
$[-5sqrt(7*3)]*[-3sqrt(7*6)]=$

$=[-5sqrt(7)sqrt(3)]*[-3sqrt(7)sqrt(6)]=$

$=[-5sqrt(7)sqrt(3)]*[-3sqrt(7)sqrt(3)sqrt(2)]=$

Multiplying:

$=15*7*3*sqrt(2)=315sqrt(2)$

How do you simplify -5sqrt21*-3sqrt42-5sqrt21*-3sqrt42?