Question 990080
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x=one number; y=other number
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x=2y+40
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{{{xy=2(x+y)+40}}}
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{{{(2y+40)(y)=2x+2y+40}}}
{{{2y^2+40y=2(2y+40)+2y+40}}}
{{{2y^2+40y=4y+80+2y+40}}}
{{{2y^2+40y=6y+120}}}
{{{2y^2+34y-120=0}}}
{{{y^2+17y-60=0}}}
{{{(y+20)(y-3)=0}}}
{{{y+20=0}}} {{{OR}}} {{{y-3=0}}}
{{{y=-20}}} {{{OR}}} {{{y=3}}}
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If y=-20:
x=2y+40
x=2(-20)+40
x=-40+40
x=0
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Solution 1: (0,-20)
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CHECK:
{{{xy=2(x+y)+40}}}
{{{(0)(-20)=2(0+(-20))+40}}}
{{{0=-40+40}}}
{{{0=0}}}
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If y=3:
x=2y+40
x=2(3)+40
x=6+40
x=46
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Solution 2: (46,3)
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CHECK:
{{{xy=2(x+y)+40}}}
{{{(46)(3)=2(46+3)+40}}}
{{{138=2(49)+40}}}
{{{138=98+40}}}
{{{138=138}}}
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ANSWER: The numbers are 0 and -20, or 46 and 3.