Some parabolas of the form y=x
2+bx+c have three distinct intercepts (two x and one y). If for all such parabolas a circle is drawn through these three points, they will have a point in common.
Prove this assertion and find the point.
(In reply to
re: Solution by Jer)
Thanks, but now taking another look I think I have made an error about the claim that the vertex is always in the circle.
I'll have to take another crack at it sometime.