Area and perimeter of a rectangle (including squares)

Perimeter
Perimeter is the distance around a polygon.
To find the perimeter of a polygon, add the length of each side of the polygon. Perimeter interactive explorer Extra practice 
Area
Area is the number of square units inside a polygon.
To find the area of a rectangle, multiply the length by the width. The formula is: a=lw, where a is the area, l is the length, and w is the width. A square is a rectangle with 4 equal sides. To find the area of a square, multiply the length of one side by itself. The formula is: a=s2 where a is the area, s is the length of a side, and 2 means square the side length. Area ineractive explorer Extra practice 