Respuesta :

Perfect squares:

1^2 = 1
2^2 = 4
3^2 = 9
4^2 = 16
5^2 = 25
6^2 = 36
...

Which of these perfect squares are 5 units apart?
Well, simply do the subtraction to find out.

36 - 25 = 11
16 - 9 = 7
9 - 4 = 5

Ah we found the squares! 9 and 4.