Answer:
The correct option is III: 4.5 cm.
Step-by-step explanation:
The area of a square is the following:
[tex] A = b^{2} [/tex] (1)
Where:
A: is the area
b: is the side of the square
We have that the area is 20 cm², hence by solving equation (1) for b we can find the side:
[tex] b = \sqrt{A} = \sqrt{20 cm^{2}} = 4.5 cm [/tex]
Therefore, the correct option is III: 4.5 cm.
I hope it helps you!
