若3x-2y=15,3y-2x=11,求x+y

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) 3x-2y=15 3y-2x=11 求x+y 若x-y/x+y=5,求x-y/2x+2y+5x+5y/3x-3y的值 若（x-2）*2+15y-11=0,求-3(2x-y)-{7x-〔6x+2y-（10x-8y）〕 若(x-2)的平方+15y-11=0,求代数式-3(2x-y)-{7x-[6x+2y-(10x-8y 3(x+y)-4(x-y)=11,2(x-y)+5(x+y)=27 若(x-y)/(x+y)=3 则(x+2y)/(6x-7y)等于 若x、y满足2x+y=6,x-3y=1,求7y(x-3y)²-2(3y-x)³的值 已知2x+2y=-8,4x+y=15求（x-y)^-(3x+2y)^ 若X,Y互为相反数,且(X+Y+3)(X-Y-2)=0,求X,Y的值? 若根号x+y-3+绝对值xy+x+y-2=0,求x/y+y/x