The Area of a Plane Surface
The area of a surface refers to the total size of the plane surface. This may be obtained taking into consideration of two edges of the plane surface being measured.
Area of a rectangle
Area = length x width
Area of a square
Area = length x width
Area of a triangle
Area = ½ x base x height
The unit of area of a plane surface is squared millimetres (mm2), squared centimetres (cm2), squared metres (m2) or squared kilometres (km2).