x+y=36； 6000x+4000y=100500 求得数.这是二元一次方程组.

x-y/x-x+y/y-(x+y)(x-y)/y² y/x=2 若(X×X+Y×Y)(X×X+Y×Y-5)=36,则X×X+Y×Y＝ 化简 x / y(x+y) - y / x(x+y) = x+x+x+y=52 y+y+y+x=36求x x(x+y)(x-y)-y(y+x)(y-x)=(x-y)( )填空 x+x+y+y+y=21 ,x+x+y+y+y+y+y=27 ,x ,y=? x+x+y+y+y=21 ,x+x+y+y+y+y+y=27 ,x ,y=? y=x(x 3(x+y)+2(x-y)=36 4(x+y)-5(x-y)=2 X+X+X+X+Y+Y+Y=36,X+X+Y+Y+Y=24,那么X=【】,Y等于【】.【】 y=x(14800-x)/4000 x x+x+x+x+y+y+y=56 Y+X+X=36 Y-X-X=8 X=?Y=? x+x+x+y+y=6.4 y+y+y+x+x=7.1 怎么算? 二元函数f(x,y)=x+y/x-y,求f(y/x,x/y) x-y/x+y=(x-y)²/x²-y²（x≠y) （x+y-5)*（x+y-5)+（x-y+3)=0 x*x-y*y 已知:3x-5y=0,求x/y,x-y/y,x-y/x