A and B are points on the graph y=x
^{2}+8x+7
C and D are points on the graph y=x
^{2}+8x7
and ABCD is a square.
Find all possible xcoordinates of point A
(In reply to
re: computer exploration (possible spoiler)  two more squares by Charlie)
There are 4 solutions. Charlie has found 3 via some hard crunching but there is a notsodifficult analytic solution.
Hint:
The two parabolas are rotations of each about the origin. This puts some limitations on the square.

Posted by Jer
on 20100226 15:01:36 