先化简再求值:-3(2x-y)-{7-〔6x+2y-(10x-8y)〕+x-2(3x-4y)}已知x=-1/5,y=-5
先化简再求值:-3(2x-y)-{7-〔6x+2y-(10x-8y)〕+x-2(3x-4y)}已知x=-1/5,y=-5
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-y/x+y=3,求代数式5(x-y)/x+y-x+y/2(x-y)
先化简再求值(x-y)(x-2y)-1/2(2x-3y)(x+2y),其中x=2,y=2/5
先化简在求值 (x+5y)(x+4y)-(x-y)(x+y),其中,x=-2又2/3,y=3/7
化简求值{(x=2y)(5x-2y)-(3x+2y)(3x-2y)]/4x,其中x=2,y=-1
先化简再求值X-{Y-2X+〔3X-2(2X+Y)+5Y〕},并求当X-Y=2的值
化简求值:(x+y)-(2x+1/2y)-(3x+1/6y)-(4x+1/12y)-(5x+1/20y)-.(10x+1
.先化简再求值:(2x+y)(2x+y)-(2x-y)平方其中X,Y满足X平方+Y平方-2X+4Y+5=0
已知x=1/3,y=-1/2,求代数式x-(x+y)+(x+2y)-(x+3y)+(x+4y)-(x+5y)+...-(
化简求值:已知【3x分之2-x+y分之2(3x分之x+y-x-y)】÷5x+3y=0
化简求值 -3(2x-y)-{7x-〔6x+2x-(10x-8y)〕-x-2(3x-4y)}