已知xy不等于0,且2x-3y=0,则分式2x-y x-y的值为-搜答案-搜狗做题网

x的平方-3xy+2y的平方=0(x-y)(x-2y)=0x=y或者x=2yx/y+y/x=1+1=1或者x/y+y/x=2y/y+x/2y=2+1/2=5/2.

3x2-2xy-8y2=(3x+4y)(x-2y)=0so3x+4y=0orx-2y=0x/y=-4/3or2

x-3y=0x=3yx*2-xy+y*2/x*2+xy+y*2=(9y^2-3y^2+y^2)/(9y^2+3y^2+y^2)=7y^2/13y^2=7/13

3x²-2xy-8y²=0两边同除y²得:3(x/y)²-2(x/y)-8=0(3x/y+4)(x/y-2)=0x/y=2或x/y=-4/3

解x²-2xy-3y²=0(x-3y)(x+y)=0当x-3y=0时则x=3y∴x/y=3当x+y=0时则x=-y∴x/y=-1

x+y=03x+y分之7x+3y=?=2x+x+y分之4x+3x+3y=2x分之4x=2

因为xy不为0,所以3x^2-2xy-8y^2=0可以两边同时除以y^2,得3(x/y)^2-2(x/y)-8=0即(3x/y+4)(x/y-2)=0解得x/y=2或者x/y=-4/3希望有用.

2x^2+5xy-3y^2=0(2x-y)(x+3y)=0y=2x或者x=-3y当y=2x时(x^2-y^2)/xy=x/y-y/x=1/2-2=-3/2当x=-3y时(x^2-y^2)/xy=x/y

3x²-2xy-8y²=0(x-2y)(3x+4y)=0x=2y或3x=-4yx/y=2或x/y=-4/3

3x²+3xy=03x²=-3xy因为x不等于0所以x=-y所以x：y=1：-1

2分之1或负4分之3

-2x+6xy-2y/(7x+5y)-9xy-(3x+y)=[3(x+y)-x-y]/[7x+5y-9/2(x+y)-3x-y]=2(x+y)/[-1/2(x+y)]=-4

2x2+5xy-3y2=0(2X-Y)(X+3Y)=0==>X=Y或者X=-3YXY不等于0,即X,Y都不等于0所以X:Y=X/Y=1或者-1/3

2x²-xy-3y²=0(x+y)(2x-3y)=0x=-y(舍去)或x=3y/2x/y=3/2x/y-x²/(x-y)=x/y-x²/(x²-2xy

已知x^2-4xy+3y^2=0……（1）,且xy不等于0,求x/y+y/x的值x^2-4xy+3y^2=0即（x-3y）(x-y)=0所以x=3y,或x=y当x=3y时,x/y+y/x=3+1/3=

无解

因为,x-y=3xy所以：-3x+6xy+3y/[(7x-5y)-9xy-(3x-y)]=[-3(x-y)+6xy]/[(7x-5y)-9xy-(3x-y)]=[-3*3xy+6xy]/[7x-5y-

2x²-xy-3y²=0(x+y)(2x-3y)=0x=-y,2x=3yx≠-y所以y=(2/3)x原式=(x²+2/3*x²)/(2/3*x²-4/

x^2+xy-6y^2=0化简得（x-2y)(x+3y)=0x=2y或x=-3y分别带入2x^2-3xy+y^2/5x^2-7xy+2y^2化简即可.