4(2.5x-x)=y 4x+300=y

x+x+x+y=60 .x-y=4 (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)=? y=x+4/x (x y=|-x.x+4x+5| 4x方y/(x-2y)(x+2y)怎么算[x方/x-2y]-4x方y/(x-2y)(x+2y)=? {3(x+y)-4(x-y)=4 {x+y/2 + x-y/6=1 x*x+2x+y*y-4y+5=0 x= y= 如果|X|=4 |Y|=2 且|X+Y|=X+Y 求X+Y （5x+3y)(3y-5x)-(4x-y)(4y+x)= （3x-y)(y+3x)-(4x-3y)（4x+3y)=? (x+y)^2(x-y)^2(x^4+x^2y^2+y^4)=? 化简:(x+y-4xy/x+y)*(x-y-4xy/x-y)= 4(x-y)-3(x-y)=9 5(x-y)+2(x-y)=11 3(x+y)-4(x-y)=11,2(x-y)+5(x+y)=27 x+y/2+x-y/3=6,4(x+y)-3(x-y)=-20