2x^2-3x=0 (3y+5)^2=4y^2
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5(x-y)/x+y-x+y/2(x-y)
若3x-5y=0,则x+y/x=(),x-y/y=(),2x-3y/2x+3y=( )
化简[(3x+4y)^2-(2x+y)(2x-y)+(-x+y)(5x-y)]除以-2y,其中x=-1,y=1
已知x=1/3,y=-1/2,求代数式x-(x+y)+(x+2y)-(x+3y)+(x+4y)-(x+5y)+...-(
数学题……555{(3x+y)(3x-y)-(x-5y)(5x-y)-(x-2y)²÷(-4x),x=-2.y
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
已知(x+2)^2+|x+y+5|=0,求3x^2y-[2x^2y-(2xy-x^2y)-4x^2]-xy
(4x-2y-z)-{5x[8y-2y-(x+y)]-x+(3y-10z)]=? kuai
若2x-3y=0,求5x+4y/3x-2y
已知x,y>0 2x+y+3=xy 求5x+4y最小值
x+y/2+x-y/3=6,4(x+y)-3(x-y)=-20