x-2y=0 4x+3y=22

已知3x^2+xy-2y^2=0,求{(x+y)/(x-y)+4xy/(y^2-x^2)}/{(x+3y)*(x-y)} {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 已知x*x-4xy+4y*y=0 求[2x(x+y)-y(x+y)]/(4x*x-4xy+y*y)的值? 若3x-4y=0,则x/y=______,（x-y)/y=______,（3x+2y)/(2x+3y)=_____. 已知x*x+4x+y*y-2y+5=0,则x*x+y*y=? 设实数X,Y满足2X+Y-2>=0,X-2Y+4>=0,3X-Y 若2x-3y=0,求5x+4y/3x-2y