The area of a square shape is the square of its length. The length of the square top is 20 inches
Given that:
[tex]Area = 400in^2[/tex]
[tex]Shape = Square[/tex]
The area of a square is:
[tex]Area = Length^2[/tex]
Take square roots of both sides
[tex]Length=\sqrt{Area}[/tex]
So, we have:
[tex]Length=\sqrt{400in^2}[/tex]
Take positive square roots
[tex]Length=20in[/tex]
Hence, the length of the square top is 20in (see attachment)
Read more about areas of squares at:
https://brainly.com/question/1658516