Respuesta :
Answer:
42 cm
Step-by-step explanation:
A square has 4 equal sides. To find the perimeter, add all side lengths together.
1. Set up the equation and solve
10.5 + 10.5 + 10.5 + 10.5 = 42
The answer is 42 because you add 10.5+10.5 +10.5+10.5=42 or do 10.5x4=42
