Is 18 square number

Answer 1

To see if a number is square, there has to be two whole numbers that multiply to give you that number. What times what would equal 18? List the multiples:

1 x 18 = 18

2 x 9 = 18

3 x 6 = 18

6 x 3 = 18 <--- this means we found all the multiples, because it just repeated (6x3 == 3x6)

If this was a square number, we'd see something like A x A = B, e.g., 4 x 4 = 16)

It's best to learn/memorize all the squares up to a certain point. They are very useful to recognize in higher level math courses.

1, 4, 9, 16, 25, 36, 49, 64, 81, 100, 121, 144

18 is not square.