Geometry

WALT find the Perimeter of 2D shapes

Formulae:

Perimeter of a Square = side + side + side + side or 4 x side

Example: The perimeter of a square of side  5cm = 5 + 5 + 5 + 5 = 20 cm or 4 x 5 = 20 cm

Find the perimeter of the following squares:

The perimeter of a square of side  10cm =    40cm

The perimeter of a square of side  25cm =    100cm

The perimeter of a square of side  5m =        20m

The perimeter of a square of side  50m =      200m

The perimeter of a square of side  1km =       4km

Perimeter of a Rectangle = length + width + length + width or 2 x l + 2 x w

Example: The perimeter of a rectangle whose length is 6cm and width is 4cm = 6 + 4 + 6 + 4 = 20 cm or 2 x 6 + 2 x 4= 12 + 8 = 20 cm

Find the perimeter of the following rectangles whose lengths and widths are given below:

Rectangle 1 - length is 8cm and width is 5cm

Perimeter = 26cm

Rectangle 2 - length is 10cm and width is 7cm

Perimeter = 34cm

Rectangle 3 - length is 8m and width is 6m

Perimeter = 28m

Rectangle 4 - length is 16m and width is 10m

Perimeter = 52m

Rectangle 5 - length is 4km and width is 2km

Perimeter = 12km

Evaluation: Today I Participated in a class math activity practicing my geometry.