The perimeter of a polygon is the sum of the lengths of its sides. It is the distance around the outside of the polygon.
See also area of circles, circumference of circles.
Since the sides of a square are equal, the perimeter of a square is 4 times the length of its side.
Perimeter of a square = s + s + s + s = 4s
where s is the length of one side
A rectangle has four sides, with opposite sides being equal in length.
Perimeter of a rectangle = l + l + w + w = 2(l + w),
where l is the length and w is the width of the rectangle.
Worksheet 1, Worksheet 2, Worksheet 3 to calculate the area and perimeter of rectangles.
Similar to a rectangle, a parallelogram has four sides with opposite sides being equal in length.
Perimeter of a parallelogram = l + l + w + w = 2(l + w)
where l is the length and w is the width of the parallelogram.
Worksheet to calculate the area and perimeter of parallelograms
Perimeter of a triangle = a + b + c
where a, b and c are the lengths of each side of the triangle.
A rhombus has 4 equal sides, so the perimeter of a rhombus is 4 times the length of its side.
Perimeter of a rhombus = s + s + s + s = 4s
where s is the length of one side
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a is parallel to b
Perimeter of a trapezoid = a + b + c + d
where a, b, c and d are the lengths of each side.
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