5.5x+1.5y=16 1.5x+5.5y=19
化简:【(x-y)的2次方+(x+y)(x-y)】除以2x,其中x=3,y=1.5
x+y=50 1.5x+1.1y=50
x+y=150 1.5x+1.1y=50
x+y=250,x/19+y/10=16,求x和y的值
已知x+y=-5,x*x+y*y=19求xy和(x-y)*(x-y)的值
x+x+x=15,x+y+y=19,求y-x等于几
现化简,再求值:(3x-y)(x+2y)-2(x-3y)·(x-4y),其中x=4,y=1.5
二元函数f(x,y)=x+y/x-y,求f(y/x,x/y)
[x(x-y)-y(x-y)+(x+y)(x-y)]÷2x其中x=2012 y=2013
) y=cos(x-y)
x+y=5; x^y+y^x=17
因式分解下列式子:x(x-y)+y(y-x)=?