y=x+1 x2+y2=5 怎么解,

y=x+1 x2+y2=5 怎么解, X2y2-x2-y2+1 =x2(y2-1)-(y2-1) =(y2-1)(x2-1) =(y+1)(y-1)(x+1)(x-1) 中的=x2(y2-1)-(y2-1) =(y2-1)(x2-1是怎么算出来的? 4X+3Y=5 X2+Y2=1 怎么解X2是X的平方，同理，Y2是Y的平方 解方程组(1):xy-y-2x+2=0 (2):x2-2x+y2-4x=-5方程组:xy-y-2x+2=0: x2-2x+y2-4x=-5怎么解? x2+4y2-2x+4y+5=0怎么解 x2-2xy+y2=4 x2+y2-x-y=6 解不等式x2-2xy+y2=4 x2+y2-x-y=6 解不等式 已知x,y满足（x2+y2）(x2+y2-1)=2,则x2+y2的值为多少?x2,y2表示x和y的平方 x2+y2+x+y=18 x2+y2-2x-4x=24 解方程组 解方程组 ｛3x2-y2=8 {4x2+12xy+9y2=1 {x2+2xy+y2-4=0 x2+xy+y2=4 4x2-9y2=0 x2-2xy+y2-1=0还有{x2+y2=4xy-y2+4=0x2-----x的平方 y2------y的平方 还有{2x-3y=12x2-3xy+y2-4x+3y-3=0 y=x+√(1-x2) y2=x2+(1-x2)+2x√(1-x2) 2010.09.已知x、y为实数,且(x2+y2)(x2+y2+1)=20,求x2+y2的值 已知实数x.y满足（x2+y2）（x2+y2-1）=2,求x2+y2的值 X2＋Y2＝12—X—Y 1/2*X*Y=6 这个方程组该怎么解? 解方程组①x2-y2=3x+3y②x2-xy+y2=27 x2+y2=1和x2+y2-4x+2y=4解这组方程, x-y=1 证明x2+y2+1/x2+1/y2大于等于17/2 已知x2+y2+4x-2y+5=0,求x2+2xy+y2值 已知x2+y2,x-y=5,求x2+y2和xy的值.