求以两圆x^2+y^2-2x+2y-3=0和5x^2+5y^2-x+7y-12=0的公共弦为直径的圆的方程rt(X-1)^2+(Y+1)^2=5这步怎么出来的？

以知x,y满足1/2[x-y]+[1-y]=0,求7x-3y的值 已知x-y/x+y=3,求代数式5(x-y)/x+y-x+y/2(x-y) 求过两圆x²+y²+2x-3y-9=0和x²+y²-2x+5y=0的交点 已知x-y=3,求[（x+y)(x-y)-(x-y)^2+2y(x-y)]除以的值 已知3x =2y 求x/x+y+y/x-y-y²/x²-y² 已知|x|=2,|y|=3,|x+y|=-(x+y)求x-y (x-y)/(x+y)=3求( 3x-2y-1)/(x+y-5) y=3(x-y),x=2(x-y)求x,y的值 若2/x-1/y=3,求[y/x-y/x-y(x-y/x-x+y)]/x-2y/x的值 以知:x^3-3y^2=2xy,求x+2y/x-y=? 已知2y-x=-3,求[4y(2x-y)-2x(2x-y)]/(2x-y x+y/2+ x-y/2=6 2(x+y)-3x+3y=24 求X Y {(x+y)/2+(x-y)/3=1,(x+y)-5(x-y)=2.求x=?,y=? x-y/x-x+y/y-(x+y)(x-y)/y² y/x=2 几道比例线段题目已知两实数a,b满足a^2-4ab+4b^=0,求(a+b)/a已知x/2=y/3,求(x-y)/y ,(x+y)/y ,(x+y)/(x-y) 求以两条直线l1:3x+2y+1=0,l2：5x-3y-11=0交点为圆心,且与直线3x+4y-20=0相切的圆的方程 以知X+Y=4,X*2+Y*2=10,求X*3+Y*3,X*4+Y*4的值 已知两圆x+y-2x+10y-24=0和x+y+2x+2y-8=0.求公共弦的长度