根据4x=3y和x+4.8=4x,推算出2x=( ),3y=( )
已知方程组4X+3Y=6和3X+4Y=15,不解出X,Y,求(X+Y)除以(X-Y)的值.
{3(x+y)-4(x-y)=4 {x+y/2 + x-y/6=1
x+y/2+x-y/3=6,4(x+y)-3(x-y)=-20
{(x+y)/2+(x-y)/3=6 4(x+y)-3(x-y)=-20
4(x+y)-3(x-y)=-20,2/x+y+3/x-y=6
3(x+y)-4(x-y)=11,2(x-y)+5(x+y)=27
(x+y)(x+2y)(x+3y)(x+4y)=-40
解方程组3(x+y)-4(x-y)=4和(x+y)/2+(x-y)/6=1
已知x和y满足3x+4y=2,x-y
已知X和Y满足3X+4Y=2,X-Y-1/7
已知x/2=y/3=z/4,求下列各式 (1)(x+y+z)/x (2)(x-y+2x/(x-y-2z)
已知x²+|y+x|=x-1/4,求(3x+y)²(2x-y)²-(4x²+y&