Answer:
Explanation:
1) to calculate the area of a square you must do: side x side so 21 x 21 = 441
2) The perimeter is calculated by: side x 4
So to find the length of a side, you divide 16 by 4.
Next, you have to calculate the area of this square with a side of 16 cm.
You just have to do 16 x 16
3) The formula to calculate the perimeter of a rectangle is: Length x Width
So you divide 100 by 20 and you get the length of your rectangle