x²+2xy+y²-y²+3y=0
(x+y)²-y²+3y=0
x+y=y²²*-6y²y+9y²
x=y²²-6yy²+9y²-y
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x+y=56
-> y=56-x
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x=(56-x)²²-6(56-x)(56-x)²+9(56-x)²-(56-x)
x=(56²-112x+x²)(56²-112x+x²)-(336-56x)(56²-112x+x²)+(28224-1008x+9x²)-56-x
so, jetz kannst du weiterrechenen
*²²= hoch 4
:wink: