Discusses the properties and types of triangles, explaining that a triangle is a closed figure with three sides and angles. It categorizes triangles into equilateral, isosceles, scalene, obtuse ...

You'll be using Sketch 1 of this file which has three different types of triangles - scalene, isosceles, equilateral. Each triangle type has a different colour (pink for scalene, red for equilateral, ...

Angles in triangles All triangles have internal angles that add up to 180°, no matter the type of triangle.