Understanding Perimeter of Polygons

The video tutorial by The Maths Guy explains how to find the perimeter of polygons. It begins with an introduction to polygons, defining them as 2D shapes with straight, closed edges. The tutorial distinguishes between regular and irregular polygons and outlines steps to find their perimeters. For regular polygons, a formula is introduced: perimeter equals the number of sides multiplied by the length of a side. Examples are provided for both regular and irregular polygons, including how to handle missing lengths. The video concludes with a summary and practice questions.

What defines a polygon as regular?

• It is a 3D shape.

• All sides and angles are equal.

• It has at least one right angle.

• It has curved edges.

Which of the following is NOT a characteristic of an irregular polygon?

• It is a closed shape.

• It has sides of varying lengths.

• All sides are of equal length.

• It has different angles.

How do you calculate the perimeter of a regular polygon?

• Subtract the length of one side from the total length.

• Multiply the number of sides by the length of one side.

• Add all the angles together.

• Divide the total length by the number of sides.

What is the perimeter of a square with each side measuring 9 meters?

• 18 meters

• 27 meters

• 45 meters

• 36 meters

Why can't a formula be used to find the perimeter of an irregular polygon?

• Because it has curved sides.

• Because it has different side lengths.

• Because it is not a closed shape.

• Because it has equal angles.

What is the perimeter of an irregular polygon with sides measuring 5 cm, 8 cm, 7 cm, and 7 cm?

• 31 cm

• 29 cm

• 25 cm

• 27 cm

When dealing with missing lengths in a polygon, what should you do first?

• Use a formula to find the missing lengths.

• Guess the missing lengths.

• Ignore the missing lengths.

• Look for clues in the given information.

If one side of a polygon is 2 cm and the opposite side is missing, what can you infer?

• The missing side is 5 cm.

• The missing side is 4 cm.

• The missing side is 2 cm.

• The missing side is 3 cm.

What is the first step in finding the perimeter of any polygon?

• Find the longest side.

• Identify if it is regular or irregular.

• Calculate the area.

• Count the number of angles.

What should you remember to include when stating the perimeter?

• The type of polygon.

• The number of sides.

• The color of the polygon.

• The unit of measurement.