SOLUTION: The circles (x+1)^2+(y-1)^2=9 and (x-3)^2+(y+1)^2=9 are overlapped. Find the point of intersections of the circles.

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Question 1168235: The circles (x+1)^2+(y-1)^2=9 and (x-3)^2+(y+1)^2=9 are overlapped. Find the point of intersections of the circles.
Answer by mananth(16946) About Me  (Show Source):
You can put this solution on YOUR website!
The circles (x+1)^2+(y-1)^2=9 and (x-3)^2+(y+1)^2=9 are overlapped. Find the point of intersections of the circles.
Since they intersect, there must be common points
we equate both
(x+1)^2+(y-1)^2=9 = (x-3)^2+(y+1)^2
x^2+2x+1+y^2-2y+1 =x^2-6x+9+y^2+2y+1
2x-2y+1 = -6x+2y+9
8x-4y=8
y=2x-2
Circle equation
x^2+2x+1+y^2-2y+1 =9
x^2+2x+y^2-2y =7
substitute y =2x-2
x^2+2x+(2x-2)^2-2(2x-2)=7
x^2+2x+4x^2-8x+4-4x+4=7
5x^2-10x+1=0
Solve for x by formula method to get value of x (two values )
substitute x in y=2x-2 to get y.