Choose the known values, enter them, and calculate the diagonal of rectangles, squares, or other shapes instantly and accurately.
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The diagonal calculator helps you find the diagonal, area, perimeter, and diagonal angles of a rectangle. Simply enter any two known values (length & width, area & one side, or perimeter & one side) to calculate the diagonal and other properties.
A Rectangle is a quadrilateral having four angles and all the angles are 90 degrees. The opposite sides of the rectangle are parallel and equal in length. The adjacent sides of the rectangle are different in length, but the diagonals are equal in length and intersect in the middle point of the rectangle. We need to enter the length and width in the rectangle diagonal calculator to find the diagonal of the rectangle.

You can calculate the diagonal using the Pythagorean theorem:
Diagonal: D = √(l² + w²)
Area: A = l × w
Perimeter: P = 2(l + w) = 2l + 2w
We can find diagonal of a rectangle as: Diagonal = √(l² + w²) Where: I = Length of the Rectangle W = Width of Rectangle
Area of a Rectangle:
We can find the Area of the Rectangle by multiplying the length and width: Area = l× w
The Perimeter of a Rectangle:
The perimeter of the rectangle can be measured by the given formula:
Perimeter = 2l + 2w=2(l+w)

We can encounter various possibilities to find diagonal of a rectangle.
From Area and Length:
First, we have to find the length by the given formula:
l= A /w
Then,
P = 2l + 2w
Diagonal length of a rectangle = √(l² + w²)
From Area and Width:
First, we have to find the width:
w= A / l
P = 2l + 2w
The diagonal measurement of a rectangle can be done as:
Diagonal = √(l² + w²)
From Perimeter and Length:
w = (P - 2l) / 2
Area = l× w
Diagonal = √(l² + w²)
From Perimeter and Width:
l= (P - 2w) / 2
Area = l× w
Diagonal = √(l² + w²)
Measure the length of the diagonal, area, and perimeter of a rectangle whose length is 4 units and width is 3 units.
Sol:
Substituting the values in the below equation
Diagonal = √(l² + w²)= √(4² + 3²) = √(25²)
The rectangle diameter = 5 units.
Length of diagonal of a rectangle= 5 units.
Area of rectangle = l× w
Area of rectangle = 4× 3 = 12 unit²
Perimeter of the rectangle = 2l + 2w
Perimeter of the rectangle = 2(4) + 2(3)
The perimeter of the rectangle = 8+ 6
The perimeter of the rectangle = 14 units
Stick to the following steps for precise calculations by the diagonal measurement calculator
Input:
Output:
Our Diagonal of a Rectangle Calculator provides you with the following values:
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