# How Many Sides Does a Rectangle Have?

A quadrilateral with four sides is a rectangle. The opposing sides of a rectangle are parallel and of equal length. As a result, a rectangle also qualifies as a parallelogram.

This quadrilateral geometry features four right angles, or angles that are each 90 degrees, on each side. A rectangle’s inside angles add up to 360 degrees. The intersection of its two equal diagonals lies in the middle of the rectangle.

Area, perimeter, and diagonal lengths are a few crucial rectangle-related formulas. The area formula for a rectangle is length times width, or l x w. A rectangle has a length and a width. The diagonal length is calculated by taking the square root of the sum of the squares of the width and length, respectively, and multiplying it by the perimeter, which is provided as 2(l + w).

Misha Khatri
Misha Khatri is an emeritus professor in the University of Notre Dame's Department of Chemistry and Biochemistry. He graduated from Northern Illinois University with a BSc in Chemistry and Mathematics and a PhD in Physical Analytical Chemistry from the University of Utah.