In another problem, we found the area of a parallelogram whose diagonals were perpendicular using the lengths of those diagonals and the lengths of one of its sides. We actually only needed the … [Read more...] about Find the area of a parallelogram using diagonals

# Area of Geometric Shapes

The area of a geometric shape is a property that describes how much space it takes up.

Regular geometric shapes like circles, parallelograms and triangles have simple formulas that give their area.

The area of irregular shapes can sometimes be computed by reducing it into several regular shapes.

Some common area formulas:

For triangles: Area = (h x b) /2

For rectangles: Area = h x w

Since a square is a special type of rectangle, its area is given by the same formula. But since in the square's case the width is the same as the hight, this becomes Area = a x a = a^{2}

A circle's area is given by the formula A_{circle}=π*r^{2}

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*Now that we've explained the basic concept of area in geometry, let's scroll down to work on specific geometry problems relating to this topic.*

## Area of a Right Triangle

This post will be a short and simple but very useful application of the general formula for finding the area of a triangle, to the specific case of a right triangle. Problem ΔABC is a right … [Read more...] about Area of a Right Triangle

## Area of Rhombus

There are several ways to find the area of a rhombus. A rhombus is a special kind of parallelogram, in which all the sides are equal. Because it is a parallelogram, we can find its area using the … [Read more...] about Area of Rhombus

## Area of Parallelogram Given Diagonals and a Side

The basic formula for calculating the area of a parallelogram is the length of one side times the height of the parallelogram to that side. But what do we do when we do not have these measurements … [Read more...] about Area of Parallelogram Given Diagonals and a Side

## Ratio of Areas of Triangles With the Same Height

As the area of a triangle is given by the formula (base · height)/2, triangles with the same height will have areas whose ratio is the same as the ratio of their bases: In the following … [Read more...] about Ratio of Areas of Triangles With the Same Height

## Area of Semicircle

In today's lesson, we will discuss the formula for finding the area of a semicircle. A semicircle is half of a circle - a shape like this: It is formed by drawing the diameter of a circle - a … [Read more...] about Area of Semicircle

## Finding the Ratio of Triangle Areas With the Same Base

The area of a triangle is given by the formula (base · height)/2. Triangles that have the same base will have areas whose ratio is the same as the ratio of their heights: In the above drawing, … [Read more...] about Finding the Ratio of Triangle Areas With the Same Base

## Area of a Kite

Using the technique of partitioning a complex shape into simpler geometric shapes, with known formulas for their areas, we can find a simple formula for the area of a kite. -It is the product of the … [Read more...] about Area of a Kite

## Find the Area of the Shaded Region

In today's lesson, we will use the strategy of calculating the area of a large shape and the area of the smaller shapes it encloses to find the area of the shaded region between them. Sometimes we … [Read more...] about Find the Area of the Shaded Region

## Find the Area of a Circle from 3 Points

Three points in a plane that are not all on the same line (not collinear) define a triangle, and any triangle can be circumscribed by a circle. So three points in a plane also define a circle. In this … [Read more...] about Find the Area of a Circle from 3 Points