Triangles, Quadrilaterals and Polygons

Success Criteria

At the end of this chapter, students are able to:

  1. State the names and properties of special triangles, quadrilaterals and polygons.

  2. Calculate the sum of interior angles and exterior angles for triangles, quadrilaterals and other polygons.

  3. Solve geometrical problems involving the properties of triangles, quadrilaterals and polygons.

  4. Justify with reason... (AO3).

Triangles

Triangles are geometrical objects that are formed by 3 line segments with 3 interior angles.

Sierpinski's Triangle

There are many examples of shapes in the world around us.

The Esplanade

The Esplanade

Snooker Rack

Pyramids of Giza

NDP Pennants

Can you find some examples of geometrical shapes around you?

Next: Let's look at different types of triangles.