9514 1404 393
Answer:
see attached
Explanation:
In general, the only way to divide a square array of dots into two triangular arrays of dots is the way it was done in the example shown in the problem statement. The dividing line is drawn next to the longest diagonal.
So, for 25 dots, you make a 5×5 array and draw the line next to the corner-to-corner diagonal. Same for a 6×6 array of 36 dots.