若方程组3x-2y=17 2x-3y=13 则x+y= x-y= x= y=

若方程组3x-2y=17 2x-3y=13 则x+y= x-y= x= y= 若(x-y)/(x+y)=3 则(x+2y)/(6x-7y)等于 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(x+y)(x-2y)=-5 (x-y)(x+2y)=7 已知X-Y/X+Y=3,求代数式2(x-y)/X+Y-3X+Y/X+Y 已知x-y/x+y=3,求代数式5(x-y)/x+y-x+y/2(x-y) 已知x,y的值满足方程组x+2y=3,x-y=-2,求x/(x-y)²+x²-y²/(x+ 方程组x-2y=8,3x-4y=5,x=?,y=? 解方程组｛ 3x-4y(x-y)=3 { 2x-3y=1 如果方程组3x+y=k x+3y=2的解x,y 解方程组：{x+|3x-y|+3y=15 2x+y=6 解方程组x+y/3=x-y/4 2x+3y=11