150X+140Y≤3000 (1) X≤Y (2) 3X+2Y=50 (3) 怎样解
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
2X(x-150)=5X(3y+50) 10%x+6%y=8.5%X800怎样解?
(3x-y)^2+(3x+y)(3x-y),x=1,y=-2
{3(x+y)-4(x-y)=4 {x+y/2 + x-y/6=1
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)
2(x+y) 3x+3y=24 x+y/2x x y/2y= 1
y=-3x,-2≤x
化简[(3x+4y)^2-(2x+y)(2x-y)+(-x+y)(5x-y)]除以-2y,其中x=-1,y=1
解方程组2(x-y)/3-x+y/4=-1 6(x+y)-4(x-y)=12 怎样能简便一点解
解方程组:(x+3)(y-2)=(x-3)(y+10),(x+1)(y+3)=(x-2)(y+12)
解方程组{(x-2)(y+3)=(x+1)(y-1) {(x+1)(y+1)=(x-1)(y+5)