1.2×3×(10-6)=24-6×[(2×3)-10]=24(3-6)(2-10)=242.∵|3-y|+|x+y|=0∴|3-y|=0,|x+y|=0解得y=3,x=-3x-y除以xy=(-3-3)÷(-3×3)=2/3
1.2x3x(-6+10)=242.y=3,x=-3,(x-y)/xy=2/3
2:y=3 x=-3 3-(-3)=6 3×(-3)=-9 6÷-9=-2/3