已知xy\/x+y=2,求3x-5y+8y\/-x+3xy-y的值。
你的题目是前面的是分子,后面的是分母吗?如果是则解答过程为 如有疑问欢迎追问
已知xy\/x+y=2,求3x-5x+3y\/-x+3xy-y的值。
xy\/(x+y)=2 xy=2(x+y)3x-5xy+3y\/-x+3xy-y =[3(x+y)-5xy]\/[-(x+y)+3xy]=[3(x+y)-5*2(x+y)]\/[-(x+y)+3*2(x+y)]=-7(x+y)\/(5(x+y)=-7\/5
已知xy\/x+y=2,求3x-5x+3y\/-x+3xy-y的值。
=[3(x+y)-5xy]\/[-(x+y)+3xy]=(3\/2xy-5xy)\/(-1\/2xy+3xy)=(3\/2-5)\/(3-1\/2)=-7\/5 你是不是分子分母写倒了 呵呵 若是xy 是分母 x+y是分子 (x+y)\/xy=2 x+y=2xy (-x+3xy-y)\/(3x-5xy+3y)=[-(x+y)+3xy]\/[3(x+y)-5xy]=(-2xy+3xy)\/(6xy-5xy)=xy...
已知xy\/x+y=2,求代数式3x-5y+3y\/-x+3xy-y的值
因为xy\/(x+y)=2 →(x+y)=xy\/2 则(3x-5y+3y)\/(-x+3xy-y)=[3(x+y)-5y]\/[-(x+y)+3xy]=[3*(xy\/2)-5y]\/[-xy\/2 +3xy]=(3xy\/2 -5y)\/(5xy\/2)=3\/5-2\/x
已知xy除以x+y=2,求代数式3x-5xy+3y除以﹣x+3xy-y的值
xy\/(x+y)=2 , xy=2(x+y)(x-5xy+3y)\/(﹣x+3xy-y)=(x-5*2(x+y)+3y)\/(﹣x+3*2(x+y)-y)=(3x-10x-10y+3y)\/(-x-6x-6y-y)=(-7x-7y)\/(-7x-7y)=1
已知xy x+y =2 ,求代数式 3x-5xy+3y -x+3xy-y 的值
∵ xy x+y =2∴xy=2(x+y)∴原式= 3x-5×2(x+y)+3y -x+3×2(x+y)-y = -7x-7y 5x+5y = - 7 5
...X+3XY--Y) 提示把XY 和 X+Y看作整体 XY等于 2(X+Y)
(3X--5XY+3Y)\/(--X+3XY--Y)=【3(X+Y)-5XY】\/【3XY-(X+Y)]上下同时除以(X+Y)得出:【3-5XY\/(X+Y)】\/3XY\/(X+Y)-1 =(3-10)\/(6-1)=-7\/5 XY\/(X+Y)=2
已知xy分之x加y等于2,求3x减5xy加3y分之负x加3xy减y.急快...
xy分之x加y等于2 ∴x+y=2xy 3x减5xy加3y分之负x加3xy减y =[-(x+y)+3xy]\/[3(x+y)-5xy]=(-2xy+3xy)\/(6xy-5xy)=xy\/(xy)=1
如果XY\/X+Y=2,求代数式3X-5Y+3Y\/-X+3XY-Y的值为 ?没错!
"确定题目没错 分子的"-5Y"和"+3Y"是同类项 若是"代数式3X-5XY+3Y\/-X+3XY-Y的值为 "则答案是 3X-5XY+3Y\/-X+3XY-Y =(3X-5XY+3Y)\/(-X+3XY-Y)=[3(X+Y)\/(XY)-5]\/[3-(X+Y)\/(XY)]=(3\/2-5)\/(3-1\/2)=-7\/5 =-1.4 ...
已知多项式x+y分之xy=2,求代数式-x+3xy-y分之3x-5xy+3y的值
x+y分之xy=2,则 xy\/(x+y)=2 xy=2x+2y (-x+3xy-y)分之(3x-5xy+3y)=(3x-5xy+3y)\/(-x+3xy-y)=[3x-5(2x+2y)+3y)\/[-x+3(2x+2y)-y]=(3x-10x-10y+3y)\/(-x+6x+6y-y)=(-7x-7y)\/(5x+5y)=[-7(x+y)]\/[5(x+y)]=-7\/5 =-1.4 ...