x2 + y2 =107 2xy+3x+3y =73
Find the value of x+y
x^2+y^2+2xy=107+2xy (x+y)^2=2xy+107=73-3x-3y+107=180-3x-3y (x+y)^2=-3(x+y)+180 let a=x+y a^2+3a-180=0 (a+15)(1-12)=0 a=-15, or a=+12<o:p></o:p>
Therefore x+y = -15 or +12<o:p></o:p>
blackjack
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flooble's webmaster puzzle
Solution
