Question

X^2-7xy+y^2=9; 3x-2y=1

Answer 1

x²+7xy+y²=93x-2y=1    2y=3x-1   y=0.5(3x-1)x²+7x*0.5*(3x-1)+0.25(9x²-6x+1)=9x²+10.5x-3.5x+2.25x²-1.5x+0.25-9=0
3.25x²+5.5x-8,75=013x²+22x-35=0    D=22²+4*13*35=2304   √2304=48x1=1/26[-22+48]=1x2=1/26[-22-48]=-35/13
x1=1  y1=0.5(3*1-1)=1x2=-35/13   y2=0.5(-35*3/13-1)=-105/26-13/26=-59/13

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