解方程组:(x+1)/20=(y+1)/21=(x+y)/17
解方程组{ 3x-4y(x-y)=3 { 2x-3y=1
解关于X,Y的方程组 {x+y=a (a-1)x+y=5
已知方程组4x+2y=1,20x+8y,求x,y
解方程组:解方程组:|X+Y|=1|X|+2|Y|=3
解方程组{(x-2)(y+3)=(x+1)(y-1) {(x+1)(y+1)=(x-1)(y+5)
要求 解方程组:{(X-1)(Y+1)=(X+1)(Y+1){X(2+Y)-6=Y(X-4)
换元法解方程组3/x+y+2/x-y=17/5 2/x+y-5/x-y=1
解方程组{4/x+y+6/x-y=3, 9/x-y-1/x+y=1
解方程组:{4/x+y+6/x-y=3 9/x-y-1/x+y=1}
数学书解方程组{2(x+y)-(x-y)=3,(x+y)-2(x-y)=1
用加减法解方程组:{(x+y)/6+(x-y)/10=3 (x+y)/6+(y-x)/10=-1
2(x+y)-3(x-y)=1 6(x+y)+7(x-y)=51 解方程组