SOLUTION: |xy|=|x||y|

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Question 947081: |xy|=|x||y|
Answer by rothauserc(4718) About Me  (Show Source):
You can put this solution on YOUR website!
|xy|=|x||y|
This equality can be verified by considering cases. One of the four possible cases is checked as follows
case 1) suppose x < 0 and y > or = 0, then xy < or = 0 and
|xy| = -(xy) = (-x)(y) = |x| |y|
The other three cases are similarly checked.