Grade 8 → Geometry → Understanding Quadrilaterals → Types of Quadrilaterals ↓
Square
In geometry, the square is one of the simplest and most symmetrical types of quadrilaterals. Understanding the properties and characteristics of the square can help in understanding more complex concepts in geometry. The square is a special type of quadrilateral that is equilateral and right-angled, meaning that all sides are the same length and all angles are the same size.
Definition of class
A square is a four-sided polygon, known as a quadrilateral, where:
- All the four sides are of equal length.
- All four angles are right angles (90 degrees).
- The opposite sides are parallel.
Mathematically, a square can be defined using certain formulas and properties, with each side represented by s
.
Properties of the square
Some of the important properties of class are as follows:
- Equal sides: All four sides of a square are of equal length.
- Right angle: Each angle in a square is 90 degrees.
- Diagonal relation: A square has two diagonals and their lengths are equal. Each diagonal bisects the angle through which it is drawn.
- Symmetry: A square has four lines of symmetry and rotational symmetry of order 4.
Mathematical Formulas
The perimeter and area of a square are calculated as follows:
Circumference
Ifs
is the length of a side of a square, then: Perimeter,P = 4s
.
Area
The areaA
of a square is given by:A = s²
.
Diagonals
The length of each diagonal in a square,d
, can be calculated as follows:d = s√2
.
Visual Example
Consider a square with one side inscribed s
:
Each side of the square is marked s
, and the diagonals intersect each other at the centre.
Understanding through examples
Example 1
If each side of the square is 5 cm, find the perimeter.
Solution: Use the formula for the perimeterP = 4s
. Here,s = 5
cm. Hence,P = 4 × 5 = 20
cm.
Example 2
Given a square with an area of 100 sq. cm, calculate the length of one of its sides.
Solution: Use the formula for areaA = s²
. GivenA = 100
cm². So,s² = 100
. Therefore,s = √100 = 10
cm.
Applications of classes
Squares are used in a variety of real-life contexts and mathematical applications:
- Tiling and Flooring: Square tiles are used in building construction.
- Board games: Games like chess and Sudoku have boards made up of square grids.
- Computer graphics: Pixels in digital images are usually square.
Interesting facts about squares
Understanding squares also reveals some interesting mathematical facts:
- A special example is a square, rhombus and rectangle.
- The diagonals of a square not only bisect each other but also intersect at right angles (90 degrees).
- Square can be found as the largest quadrilateral inside the circle.
Conclusion
The square is a fundamental shape in geometry that has unique and easily recognizable properties. Knowing how to recognize and calculate its dimensions is important for solving a variety of mathematical problems. Because of their symmetry and simplicity, squares are ubiquitous in both theoretical mathematics and practical applications.