2x加y等于7便无悔y的表述形式-搜答案-智慧作业帮

1/2再答：再问：谢谢了，问题解决了

该试可以这样写：(x-1)的平方加(y+2)的平方等于0.所以X等于1,Y等于-2.那2X加Y等于0了.

x^2-2x+y^2+6y+10=0x^2-2x+1+y^2+6y+9=0(x-1)^2+(y+3)^2=0x-1=0,y+3=0x=1,y=-3(x-y)/(x+y)=4/(-2)=-2

1/x-1/y=2(-x+xy+y)/(2x+7xy-2y)=(-x+xy+y)÷xy/(2x+7xy-2y)÷xy=(-1/y+1+1/x)/(2/y+7-2/x)=(1/x-1/y+1)/[-2(

x^2+y^2-2x+6y+10=0(x-1)^2+(x+9)^2=0欲等式成立x=1,y=-9于是x+y=-8

x^2+y^2+1/2=x+y(x-1/2)^2+(y-1/2)^2=0x=1/2y=1/2

x^2+2xy+y^2=25===>(x+y)^2=5^2===>x+y=±5(x-y)^2-3x+3y+2=0===>(x-y)^2-3(x-y)+2=0===>[(x-y)-1]*[(x-y)-2

均值不等式再问：怎么解？？再答：你发图我看看再问：再问：会不会啊再答：再答：→_→再问：设不等式mx平方减2x减m加1＜0对于满足m的绝对值小于等于2的一切m值都成立，求x的取

x+y=7y=7-xxy=x(7-x)=12x=3或4x=3,y=4或x=4,y=3x-y=1或-1

x方+y方+5/4=2x+y(x方-2x+1)+（y方-y+1/4)=0(x-1)方+（y-1/2)方=0x=1,y=1/2xy/(x+y)=1/3

y=6-xy²=2+7x所以36-12x+x²=2+7xx²-19x+34=0(x-2)(x-17)=0x=2,x=17y=6-x所以x=2,y=4x=17,y=-11

x-y=-1(x+y)^2+2(x+3y)=7这个没错吧再问：是的再答：再答：

再问：就是把他们等于一下吗再答：嗯再答：交点就是两条直线xy都相等再答：不谢再问：哦

x^2+2xy+y^2=(x^2+xy)+(xy+y^2)=2+7=9

x^2+2xy+y^2=(x^2+xy)+(xy+y^2)=2+7=9

x+y+1=0x+y=-1（x加y）的平方减3（x加y）a=1+3a=7a=2a的平方加2=6

x+y=2x^2-y^2+4y=(x+y)(x-y)+4y=2x-2y+4y=2x+2y=2(x+y)=4

x*y=-6；x+y=1或者-1

答案是：x-y=1