x y=12 x² y²=100怎么解-搜答案-搜搜做题作业网

2元1次元是指代数或者字母的个数次则是指字母含的次数比如x的3次方这属于3次方程至于怎么解很简单x+y=3那么x=2-yxy=-3那么（2-y）y=-3yy-2y-3=0也就是(y-3)(y+1)=0

（3xy+10y)+[+5x-(2xy+2y-3x)]=3xy+10y+[+5x-2xy-2y+3x],[原式去括号]=3xy+10y+5x-2xy-2y+3x,[去括号]=3xy-2xy+5x+3x

dy/dx=(xy+3x-y-3)/(xy-2x+4y-8)=(x-1)(y+3)/(x+4)(y-2)再问：然后呢？再答：(y-2)dy/(y+3)=(x-1)dx/(x+4)已经是变量分离方程，两

x y xy=10怎么算

2xy=10xy=5

xy-12=4x+y≥2√(4xy)=4√(xy)xy-4√(xy)-12≥0(√(xy)-6)(√(xy)+2)≥0√(xy)≤-2,√(xy)≥6因为√(xy)≥0所以√(xy)≥6xy≥36所以

(-3x^y+2xy)-(4x^+xy)=-3x^y+2xy-4x^-xy=-3x^y+xy-4x^所以填上-3x^y+xy-4x^

这是二元方程,只有xy=2x+2y这一个条件的话,答案会有无穷多组的,比如x=0,y=0;x=1,y=-2等.

x-y=(x-xy)+(xy-y)=40+(-20)=20x+y-2xy=(x-xy)-(xy-y)=60希望满意!

(x+y)^2=(x-y)^2+4xy=64+4(-z^2-16)=-4z^2=0所以(x+y)^2=0所以x+y=0x-y=8x=4,y=-4z=0

x(x-y)-y(y-x)=12那么：化简得：（x+y）*（x—y)=12x、y是自然数,所以x1=2,y1=4x2=4,y2=2所以x+y-xy=-2

（4xy+12y)+[7x-(3xy+4y-x)]=4xy+12y+7x-3xy-4y+x=xy+8x+8y=xy+8(x+y)=(-2)+8*3=-2+24=22

x^2+y^2=16xy=6x^2+y^2+2xy=16+2*6=28(x+y)^2=28x+y=±2√7(x-y)^2=16-2*6=4x-y=±2联立x+y=±2√7x-y=±2可以解出来x=1+

x+y=7x=7-y(7-y)y=127y-y^2=12y^2-7y+12=0(y-3)(y-4)=0y1=3y2=4x1=4x2=3

两式相加得x=4+xy即x=4/(1-y)①两式相减得y=-1-4xy②①代入②y=-1-4y*4/(1-y)整理得y²-16y-1=0解得y=8±√65代入①,即可算出x了如有不明白,可以

解题思路：：∵x+y=0,x+13y=1，解得x=1/12,y=-1/12∴x²+12xy+13y²=1/144-1/12+13/144=14/144-1/12=2/144=1/72解题过程：已知x+

x²+xy=12 xy+y²=13

两式相加得到x+y=5,相减得y-x=1/5,故x=12/5,y=13/5xy=156/25,因为要求的都是正数,而且xy同正负,所以只考虑x,y正数即可故x²+y²=（x+y）^

16524

因为2xy+x+y=83所以4xy+2x+2y=83*2所以(2x+1)(2y+1)=165=3*5*11=1*165=3*55=5*33=11*15所以2x+1=1,2y+1=165或2x+1=3,

x²-7xy+12y²=0(x-3y)(x-4y)=0x1=3yx2=4yx=3y时原式＝9y²-3y²+y²/6y²=7/6x=4y时原式