Rectangle Perimeter

The perimeter of a rectangle is the distance around the outside. Formula: 2 × width + 2 × height, or 2(w + h).

A rectangle with width 5 and height 3 has perimeter 2(5 + 3) = 16.

In coordinate problems, perimeter = 2(|x₂ - x₁| + |y₂ - y₁|).