Perimeter of Shapes

≈ 20 min

The perimeter of a shape is the total distance all the way around it — the sum of the lengths of every side.

For a rectangle with length $l$ and width $w$ , opposite sides are equal, so

P = l + w + l + w = 2 \times (l + w).

For a square, all four sides are equal, so $P = 4 \times \text{side}$ .

Worked example. A rectangle is $6$ m long and $4$ m wide: $P = 2 \times (6 + 4) = 2 \times 10 = 20$ m.

A square has sides of $7$ cm. What is its perimeter, in cm?

A rectangular soccer field is $90$ m long and $45$ m wide. What is its perimeter, in metres?

How do you find the perimeter of a rectangle?

multiply length by width

add the lengths of all four sides

add the length and the width only

multiply one side by itself

A rectangular vegetable garden is $8$ m long and has a perimeter of $26$ m. How wide is it, in metres?