<PRE><B>Question 828379</B>
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x = volume of 100% antifreeze
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20*10 + 100x = 50(x + 10)
200 + 100x = 50x + 500
50x = 300
x = 300/50
x = 6
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drain 6 quarts and replace that volume with 100% antifreeze
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Solve quadratic equations, quadratic formula:
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Solve systems of linear equations up to 6-equations 6-variables:
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