Respuesta :

HumanBein

Answer:

18 cm.

Step-by-step explanation:

There are four sides on a square, and each side has the same measure as the other three. So, if one side measures 4.5 cm, four sides would be 4 * 4.5 = 4.5 + 4.5 + 4.5 + 4.5 = 9 + 9 = 18 cm

Hope this helps!