Here are some rules you’ll need to know about rectangles and squares:
- The perimeter of a rectangle is the sum of the lengths of its sides.
Just add them up.
perimeter = 10 + 4 + 10 + 4 = 28
- The area of a rectangle is length × width.
The area of the preceding rectangle, therefore, is 10 × 4, or 40.
Little Boxes
Here’s a progression of
quadrilaterals from least
specific to most specific:
quadrilateral is any
4-sided figure
↓
parallelogram is a
quadrilateral in which
opposite sides are parallel
↓
rectangle is
a parallelogram in which
all angles = 90 degrees
↓
square is a rectangle in
which all sides are equal
- A square is a rectangle whose four sides are all equal in length.
The perimeter of a square, therefore, is four times the length of any side. The area is the length of
any side squared.