300/X+1=300/Y 300/2Y=250/X-6/7 解方程组

2(x+y)-3(x-y)=1 6(x+y)+7(x-y)=51 解方程组 解方程组﹛2(x+y)-3(x-y)=1 6(x+y)+7(x-y)=51 解方程组(x+y)(x-2y)=-5 (x-y)(x+2y)=7 解二元一次方程组:{5(x+y)+3(x-y)=2{7(x+y)-3(x-y)=-6 要求 解方程组：｛(X-1)(Y+1)=(X+1)(Y+1)｛X(2+Y)-6=Y(X-4) 解方程组：2(x-y)/3-x+y/4=-1 ,6(x+y)-4(2x-y)=16 解二元一次方程组{3(x+y)-(x-y)=4,x+y/2+x-y/6=1 解二元一次方程组{3(x+y)-4(x-y)=4,x+y/2+x-y/6=1 解方程组3(x+y)-4(x-y)=4和(x+y)/2+(x-y)/6=1 解二元一次方程组：3(x+y)-4(x-y)=4,x+y/2+x-y/6+1 已知方程组2X+Y=6和X-3Y=1不解方程组,求7Y(X-3Y)^2-(3Y-X)^3 已知方程组{2x+y=6,x-3y=1,不解方程组,求7y(x-3y)²-(3y-x)²的值.