5x+2y=52=3x+2y=36怎么算?
已知x-y/x+y=3,求代数式5(x-y)/x+y-x+y/2(x-y)
3x+2y=36=5x+2y=72怎么算?
先化简再求值(x-y)(x+y)-(x-2y) 的完全平方+x(3x-5y)-(x-y)(x-2y),其中x=1/2 y
6(x-y)-2(x+y)=14 3(x-y)+(x+y)=5
3(x+y)-4(x-y)=11,2(x-y)+5(x+y)=27
已知X-Y/X+Y=3,求代数式2(x-y)/X+Y-3X+Y/X+Y
2x-y=8 3x+2y=5与3x+2y=1 3x-4y=-11用加减法怎么算?
方程组3X+3Y+2X-2Y=36 4X+4Y-5X+5Y=2 怎么化简啊!
(5*x+2*y)/(x+y)=3,求x与y的关系,是不是x=2y?怎么算?
化简[(3x+4y)^2-(2x+y)(2x-y)+(-x+y)(5x-y)]除以-2y,其中x=-1,y=1
3x+3y+2x-2y=36 4x+4y-5x-5y=2
3(x+y)+2(x-y)=36 4(x+y)-5(x-y)=2 解方程组