# GRE Geometry - Rectangles

A **rectangle** is a four-side figure where opposite sides are equal in length and the four angles are all right angles. The are formula for a rectangle is simply base times height, while the **perimeter** of a rectangle, or the total distance of its sides, is 2 times the length plus 2 times the width. Rectangles are fairly straight forward, and you should definitely know the area and perimeter formulas by heart. Examples of rectangles, their areas, and perimeters, where A = Area and P = Perimeter:

Notice the following facts:

- In the third rectangle, the height is
*x*and width is*y*, and the values for*x*and*y*are given, so simple substitution gives the desired area and perimeter values. - There is no relationship between the height and width of a rectangle. For example, in the first rectangle, the area is much greater than the perimeter, while in the third rectangle, the perimeter is much greater than the area.
- A square, the fourth figure, is also a rectangle in which the height and width are equal.