- Thread starter
- Admin
- #1

- Feb 14, 2012

- 3,894

-----

Let $a,\, b,\, c,\, d \in \mathbb{N} $ such that the equation $x^2-(a^2+b^2+c^2+d^2+1)x+ab+bc+cd+da=0$ has an integer solution. Prove that the other solution is integer too and that both solutions are perfect squares.

-----

Remember to read the POTW submission guidelines to find out how to submit your answers!