number differences

Heureka I think Will got this one right. :/

It is a nuance of the English language.

Will answered this question

what are two square numbers which have a difference of 85?

But you answered this question

what are two numbers which, when squared, have a difference of 85?

121 and 36

\((+11)^2 - 6^2 = 85\\ (-11)^2-6^2 = 85\)

11 and 6 or -11 and 6

I see, thank you Melody