197x 4y=111,197x=119-2y

197x 4y=111,197x=119-2y 解二元一次方程组197x+4y=111,197x=19-27y x+x+x+y=60 .x-y=4 y=x+4/x (x y=|-x.x+4x+5| (x-y) (x-2y)+(x+2y) (x-3y)-2(x-3y) (x-4y)= 7x:4y,x:y=( ):( (x-4y)(2x+y)= 5x-4y(y-x)=? x-y/x-x+y/y-(x+y)(x-y)/y² y/x=2 化简 x / y(x+y) - y / x(x+y) = y=x(x 4x方y/(x-2y)(x+2y)怎么算[x方/x-2y]-4x方y/(x-2y)(x+2y)=? x(x+y)(x-y)-y(y+x)(y-x)=(x-y)( )填空 (x+y)(x^2+y^2)(x-y)(x^4+x^4)=? x/3=y/4,求(x*x-xy)/(x*x+y*y)的值 x-y+5x-4x= ?x-y+5x-4x= ? x*x+2x+y*y-4y+5=0 x= y=