You can put this solution on YOUR website! x+y=21
xy=90
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rearrange the first equation as x = 21-y
substitute into the second equation
(21-y)y = 90
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Distribute y
21y - y^2 = 90
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0 = y^2 - 21y + 90
(y-15)(y-6) = 0
y-15=0, so y = 15
y-6=0, so y = 6
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The number are and
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Check
15+6 = 21
15(6) = 90
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