Area
Area is the amount of space a two dimensional (flat) surface takes up. It is useful because it is how much of a material is needed to make a hollow container. Area is the amount of surface covered by a close object or shape.
Some units used to measure area are square foot, square mile, square metre and square kilometre. The area of a planar figure is often written as .[1] Areas of regular shapes such as square, rectangle, triangle and circle can be calculated through formulas.[2] The area of an irregular shape can be approximated through grid or graph paper.[3]
One can use different formulas to find the area of different shapes. For example:[2]
- Area of a rectangle is the length of any two touching sides multiplied together. In other words, length times width.
- Area of a triangle is half of the base multiplied by the perpendicular height. In other words, .
- Area of a circle:
The area of a flat object is related to the surface area and volume of a three-dimensional object.
The area under a curve can be found using integration, a concept from calculus.