Rectangle - perimeter and area
Online calculator — enter the values and get the result instantly, with the formula and a worked example.
Photo
Formula & notes
A = area
P = perimeter
a = side "a"
b = side "b"
What is it
A rectangle is a four-sided polygon, or quadrilateral, with opposite sides of equal length and all internal angles equal to 90 degrees. The properties of a rectangle include diagonals that are equal in length and bisect each other. The area of a rectangle can be calculated using the formula: Area = length * width, and the perimeter can be calculated as: Perimeter = 2 * (length + width). Rectangles are fundamental shapes in geometry and are commonly used in various applications in mathematics, design, and architecture.
Calculator
cm
cm
Rectangle area
–
Perimeter
–
Diagonal u
–
Circumscribed circle radius r
–
Sides a · b
–
Interactive graph
Grab a corner or an edge and drag Re-center
Discover more
Worked example
The sides of the rectangle are, for example, a is 8 cm and b is 6 cm.
Thus
a = 8,
b = 6.
perimeter of the rectangle:
We use the formula
C = 2 * a + 2 * b
thus
C = 2 * 8 + 2 * 6
C = 28 cm
area of the rectangle:
We use the formula
A = a * b
thus
A = 8 * 6
A = 48 cm²
YOU MIGHT BE INTERESTED:
COMMENTS:
