<PRE><B>Question 292503</B>
Solve using the principle of zero products. 
(21 - 0.8x)(5 - 0.4x) = 0 
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21-0.8x = 0 or 5-0.4x = 0
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21 = 0.8x or 5 = 0.4x
x = 21/0.8 or x = 5/0.4
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x = 210/8 or x = 50/4
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x = 105/4 or x = 12 1/2
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x = 26 1/4 or x = 12 1/2
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Cheers,
Stan H.
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