20. Given the area, find the side length.

Step-by-step explanation:

Area of a square = 49a⁸b¹⁰

  Side = √49a⁸b¹⁰

           = √7²*(a⁴)²*(b⁵)²

          = (7a⁴b⁵)²

Side = 7a⁴b⁵

All of the shapes listed are polygons. I don't know if that's the answer because it could be anything like they all have at least 3 lines or 3 angles or are all closed figures but you could draw a square and rectangle or something and it'd work as long as it is a closed figure with at least 3 or more sides and angles.