Rectangle Formula

We may have come across many objects in our daily life which is rectangular in shape. Some objects of this type of shape are playground, an A4 sheet of paper, room wall, etc. In this article, we will discuss rectangles, some related terms and definitions and also rectangle formula with examples. Let’s start learning!

Rectangle Formula

What is a Rectangle?

There are many authentic and real-life purposes where we would need to calculate some measurements of various shapes. For example, suppose we are looking to sod our lawn, then we would need to know the area of our lawn in order to implant grass in it. Or, we may wish to do fencing of the playground in a rectangular shape.

Thus rectangle is a very common shape in our daily life. A rectangle is any four-sided figure with four right angles i.e. 90-degree angles and with equal length of opposite sides. If we look around us, then we can see many examples. Most likely, the room in which we are sitting in some form of a rectangle or a combination of rectangles.

To recall, a rectangle is a four-sided polygon and the length of the opposite sides is equal. A rectangle is also called an equiangular quadrilateral, as all the angles of a rectangle are right-angled. A rectangle is a parallelogram with right angles in it.

When the four sides of a rectangle are made equal, then it is called a square. We have to perform a various measurements to complete some important tasks. Some measurement in rectangle as Perimeter, Diagonal, Area, etc. of the rectangle

Some terms related to this shape are as follows:

1. Length: It is the longer side of the rectangle.
2. Breadth: It is the smaller side of the rectangle.
3. Diagonal: It is the direct straight line distance between two opposite vertices of the rectangle.
4. Perimeter: It is the sum total of all four sides of the rectangle.
5. Area: Area of the rectangle describes the amount of space covered by it. So, it will give the coverage of the rectangle as a two-dimensional plane.

Some important Rectangle Formula:

1. The perimeter of the rectangle:

P= 2 × (l+ b)

Where,

P	Perimeter
l	Length
b	Breadth

 

2. Diagonal of the rectangle:

D= \((l^2 + b^2)^\frac{1}{2}\)

Where,

D	Diagonal
L	Length
b	Breadth

 

3. Area of the rectangle:

A= l × b

A	Area
L	Length
b	Breadth

Solved Examples

Q. Find out the length of the rectangle if its area is 96 cm2 and the breadth is 16 cm.

Solution:

As we know,

Area of a rectangle = l × b

Here the area is already given in the question. So,

A= l × b

B=\(\frac{a}{l}\)

B=\(\frac{96}{16}\)

B = 6 cm

Q. Find the perimeter of a rectangle whose length and width is 20 cm and 9 cm respectively.

Solution:

Here given values in the question are,

l = 20 cm

b = 9 cm

Perimeter of Rectangle,

P = 2 × (l + b)

= 2 × (20 +9) cm

= 2 × 29 cm

Hence, the perimeter of a rectangle = 58 cm