Area

Recall that the area of any parallelogram is the base times the height.  The height is the perpendicular distance from one side to the side parallel to it.  In both a square and a rectangle, the sides are perpendicular, so two side lengths can be multiplied to find the area.

Area of a square = s·s = s2, where s is the length of one side. Area of a rectangle = L·W, where L is the length and W is the width.

The area of a rhombus, however, can be found a little differently.  Recall that earlier we found the area of one triangle made by the diagonals of a rhombus.  We were able to find this because the diagonals are perpendicular.  Using this property, the formula for that area of a rhombus is found.

Area of a rhombus =