What is the Area of a Rhombus?
The area of a rhombus can be defined as the amount of space enclosed by a rhombus in a two-dimensional space. To recall, a rhombus is a type of quadrilateral projected on a two dimensional (2D) plane, having four sides that are equal in length and are congruent. It is also known as equilateral quadrilateral because all its four sides are equal in nature.
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Area of Rhombus Formula
Different formulas to find the area of a rhombus are:
|Formulas to Calculate Area of Rhombus|
|Using Diagonals||A = ½ × d1 × d2|
|Using Base and Height||A = b × h|
|Using Trigonometry||A = b2 × Sin(a)|
- d1 = length of diagonal 1
- d2 = length of diagonal 2
- b = length of any side
- h = height of rhombus
- a = measure of any interior angle
Derivation for Rhombus Area Formula
Consider the following rhombus:
Let O be the point of intersection of two diagonals.
The area of the rhombus will be:
A = 4 × area of ∆ AOB
= 4 × (½) × AO × OB sq. units
= 4 × (½) × (½) d1 × (½) d2 sq. units
= 4 × (1/8) d1 × d2 square units
= ½ × d1 × d2
Therefore, Area of a Rhombus = A = ½ × d1 × d2
Where d1 and d2 are the diagonals of the rhombus.
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How to Calculate Area of Rhombus?
The methods to calculate the area of a rhombus are explained below with examples. There exist three methods for calculating the area of a rhombus, they are:
- Method 1: Using Diagonals
- Method 2: Using Base and Height
- Method 3: Using Trigonometry
Area of Rhombus Using Diagonals: Method 1
Consider a rhombus ABCD, having two diagonals, i.e. AC & BD.
- Step 1: Find the length of diagonal 1, i.e. d1. It is the distance between A and C. The diagonals of a rhombus are perpendicular to each other making 4 right triangles when they intersect each other at the centre of the rhombus.
- Step 2: Find the length of diagonal 2, i.e. d2 which is the distance between B and D.
- Step 3: Multiply both the diagonals, d1, and d2.
- Step 4: Divide the result by 2.
The resultant will give the area of a rhombus ABCD.
Let us understand more through an example.
Example 1: Calculate the area of a rhombus having diagonals equal to 6 cm and 8 cm.
Diagonal 1, d1 = 6 cm
Diagonal 2, d2 = 8 cm
Area of a rhombus, A = (d1 × d2) / 2
= (6 × 8) / 2
= 48 / 2
= 24 cm2
Hence, area of a rhombus is 24 cm2.
Area of Rhombus Using Base and Height: Method 2
- Step 1: Find the base and the height of the rhombus. The base of the rhombus is one of its sides, and the height is the altitude which is the perpendicular distance from the chosen base to the opposite side.
- Step 2: Multiply the base and calculated height.
Let us understand this through an example:
Example 2: Calculate the area of a rhombus if its base is 10 cm and height is 7 cm.
Base, b = 10 cm
Height, h = 7 cm
Area, A = b × h
= 10 × 7 cm2
A= 70 cm2
Area of Rhombus Using Trigonometry: Method 3
- Step 1: Square the length of any of the sides.
- Step 2: Multiply it by Sine of one of the angles.
Let us see one example.
Example 3 Calculate area of a rhombus if the length of its side is 2 cm and one of its angle A is 30 degrees.
Side = s = 2 cm
Angle A = 30 degrees
Square of side = 2 × 2 = 4
Area, A = s2 × sin (30)
A = 4 × 1/2
A = 2 cm2
Practice Question Based on Area of Rhombus Formula
Question 1: Find the area of the rhombus having each side equal to 17 cm and one of its diagonals equal to 16 cm.
ABCD is a rhombus in which AB = BC = CD = DA = 17 cm
Diagonal AC = 16 cm (with O being the diagonal intersection point)
Therefore, AO = 8 cm
In ∆ AOD,
AD2 = AO2 + OD2
⇒ 172 = 82 + OD2
⇒ 289 = 64 + OD2
⇒ 225 = OD2
⇒ OD = 15
Therefore, BD = 2 × OD
= 2 × 15
= 30 cm
Now, area of rhombus
= ½ × d1 × d2
= ½ × 16 × 30
= 240 cm2
More Topics Related to Rhombus Area:
|Construction Of Rhombus||Rhombus Lines of Symmetry|
|Rhomboid||Special Parallelograms: Rhombus, Square & Rectangle|
|Difference Between Rhombus and Parallelogram||Difference Between Square & Rhombus|
Frequently Asked Questions
What is a Rhombus?
A rhombus is a type of quadrilateral whose opposite sides are parallel and equal. Also, the opposite angles of a rhombus are equal and the diagonals bisect each other at right angles.
What is the Formula for Area of a Rhombus?
To calculate the area of a rhombus, the following formula is used:
A = ½ × d1 × d2
How to Find the Area of a Rhombus When the Side and Height are Given?
To find the area of a rhombus when the measures of its height and side are given, use the following formula:
A = Base × Height
What is the Formula for Perimeter of a Rhombus?
The formula to calculate the perimeter of an equilateral triangle is:
P = 4a units