Area is a measure of the size of a flat surface or shape. It is often expressed in square units, such as square centimeters (cm), square meters (m), or square inches (in). To calculate the area of a shape, we need to know its dimensions and apply a specific formula depending on the type of shape.
In this article, we will learn how to calculate the area of some common shapes, such as squares, rectangles, triangles, circles, and polygons. We will also use an online area calculator to find the area of any shape quickly and easily.
Area of a Square
A square is a four-sided shape with equal sides and right angles. The area of a square is equal to the length of one side squared. The formula for the area of a square is:
Area = s
where s is the length of one side.
For example, if a square has a side length of 5 cm, then its area is:
Area = 5
Area = 25 cm
Area of a Rectangle
A rectangle is a four-sided shape with opposite sides equal and right angles. The area of a rectangle is equal to the product of its length and width. The formula for the area of a rectangle is:
Area = l Ã w
where l is the length and w is the width.
For example, if a rectangle has a length of 10 m and a width of 6 m, then its area is:
Area = 10 Ã 6
Area = 60 m
Area of a Triangle
A triangle is a three-sided shape with straight sides and angles. The area of a triangle is equal to half the product of its base and height. The formula for the area of a triangle is:
Area = Â½ Ã b Ã h
where b is the base and h is the height.
The base and height can be any two sides that form a right angle. For example, if a triangle has a base of 12 cm and a height of 9 cm, then its area is:
Area = Â½ Ã 12 Ã 9
Area = 54 cm
Area of a Circle
A circle is a shape with all points at the same distance from the center. The area of a circle is equal to the product of pi (Ï) and the radius squared. The formula for the area of a circle is:
Area = Ï Ã r
where r is the radius.
Pi (Ï) is an irrational number that is approximately equal to 3.14 or 22/7. For example, if a circle has a radius of 7 m, then its area is:
Area = Ï Ã 7
Area â 3.14 Ã 49
Area â 153.86 m
Area of a Polygon
A polygon is a closed shape with many straight sides and angles. The area of a polygon can be calculated by dividing it into smaller shapes, such as triangles or rectangles, and adding up their areas. Alternatively, some polygons have specific formulas for their areas based on their properties.
The following table shows some examples of polygons and their area formulas: