Explain your p&p method of finding two integers, their squares sum being 685.
You may not use algebraic formulae, calculator or Google.
Be D3 wise to make it D1!

I started from the fact that 25^2 = 5^4 = 625, which looked promisingly close. Then 26^2 is 625 + 50 + 1 = 676. And since 685 - 676 is 9 = 3^2, then (26, 3) is a solution.  I believe that this solution and the one found by Steven Lord are the only two in positive integers.

Posted by Paul on 2018-11-19 10:21:37