[tex] \left \{ {{x+xy+3y=3} \atop {2x-xy-y=-2}} ight. [/tex]

прибавим3х+2у=1у=0,5-1,5хх+0.5х-1,5х²+1.5-4,5х-3=0-1,5х²-3х-1,5=0х²+2х+1=0(х+1)²=0х=-1у=0,5+1,5=2(-1;2)