x-80=y,(1-25%)x+30=(1+20%)y问x=?y=?
x-80=y,(1-25%)x+30=(1+20%)y问x=?y=?
分式的加减:[(x/y-y/x)除以(x+y)+x(1/y-1/x)]除以1+x/y,其中x=5,y=2
集合N={(x,y)|(x-1)^2}+(y-1)^20},M={(x,y)|x^2+y^2
已知:3x=8y.求(1)x+y/y (2)2x+3y/x-2y
若|x+2y-1|+y²+4y+4=0,求(2x-y)²-2(2x-y)(x+2y)+(x+2y)&
【(x-y)的平方+(x-y)(x+y)】除以x,其中x= -1 y=二分之一
先化简,再求值 (1)[(x-y)的平方+(x+y)(x-y)]÷2x 其中X=2010,y=2009 (2)y(x+y
若|x+y-1|+(x-y-2)²=0,求代数式(x+2y)(x-2y)-(2x-y)(-y-2x)的值.
函数图象题!(1) Y=X-1 ,Y=X ,Y=X+1(2) Y=-2X-1 ,Y=-2X ,Y=-2X+1问,(1)和
解方程组:(0.2x+0.1y)/2- (4x-y)/10=(x-y)/5+ (3x+0.5y)/30 (3x+2y-1
化简求值:【(x+Y)(X-Y)-(X-Y)的平方+2Y(2-Y)】除4Y,其中X=1 Y=2
(1)x+y=420,30%x+40%y=160×80% (2)x-y/7-x+y/6=1/2,2(x-y)-5(x+y