2y=3x,y/x=3/2=1.5一定 因此x ,y成正比例.求：y=6x 4/x=0.5/y y=x y=2/x y=5x+12y=3x,y/x=3/2=1.5一定 因此x y成正比例。求：y=6x 4/x=0.5/y y=x y=2/x y=5x+1 求 x和y的比

2y=3x,y/x=3/2=1.5一定 因此x ,y成正比例.求：y=6x 4/x=0.5/y y=x y=2/x y=5x+12y=3x,y/x=3/2=1.5一定 因此x y成正比例。求：y=6x 4/x=0.5/y y=x y=2/x y=5x+1 求 x和y的比 (x-y) (x-2y)+(x+2y) (x-3y)-2(x-3y) (x-4y)= (x+y)(x-y)+(x-y)平方-(x-y)(3x-y) 其中x=-2 y=3分之一 已知x-y/x+y=3,求代数式5(x-y)/x+y-x+y/2(x-y) (x+y)(2x-3y)=? x-y/x-x+y/y-(x+y)(x-y)/y² y/x=2 [3x^2-(x+y)(y-x)][2(-x-y)(y-x)+2x^2+3y^2],其中x=-2分之1,y=1.5 [(x-y)²+（x+y）(x-y)]/2xx=3,y=-1.5 【2(x-y)^3-8(x-y)^2(x+y)+6y(x-y)^2】/2(x-y)^2= 已知x-y=3,求[（x+y)(x-y)-(x-y)^2+2y(x-y)]除以的值 已知3x =2y 求x/x+y+y/x-y-y²/x²-y² 若2/x-1/y=3,求[y/x-y/x-y(x-y/x-x+y)]/x-2y/x的值 化简:【(x-y)的2次方+(x+y)(x-y)】除以2x,其中x=3,y=1.5 先化简,后求值:[(x-y)²+(x+y)(x-y)]÷2x,其中x=3,y=1.5 {(x+2)^2-(y-3)^2=(x+y)(x-y) {x-3y=2 (3x-y)^2+(3x+y)(3x-y),x=1,y=-2 2（x+y)-3(x-y)=3 ,4(x+y)+3(x-y)=15 x+y/2+x-y/6=5 2(x+y)-3(x-y)=-2