(y/3+y/4)÷2=y/x 请问怎样消去y 得到1/3-1/x=1/x-1/4

(y/3+y/4)÷2=y/x 请问怎样消去y 得到1/3-1/x=1/x-1/4 已知x-y=1,求[(x+2y)²+(2x+y)(x-4y)-3(x+y)(x-y)]÷y的值 (x-y) (x-2y)+(x+2y) (x-3y)-2(x-3y) (x-4y)= 2x-y=2,求[(x²+y²)-(x-y)²+2y(x-y)]÷4y [(x+y)(x-y)-(x-y)²+2y(x-y)]÷4y x²/xy-x/y 3x/4x+y - x-2y/4x+y (1-y/y+x)÷x/y²-x² 请问如何化简(4x-y)/x^2y^2 - (x+y)/xy^3 请问算到4x/y=3y/x后怎么算出x,y, 请问 0=-5x+y-1 与 1=4x-3y+2 x*y的值是多少 4x-3y/x-2y÷6y-8x/y-2x 2（x+y)-3(x-y)=3 ,4(x+y)+3(x-y)=15 {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)-2(x-y)=11 4(x+y)+3(x-y)=9 3(x+y)+2(x-y)=36 4(x+y)-5(x-y)=2 （x+y）/2- x-y/2=6 3(x+y)=4(x-y)