An isosceles triangle with angles of 50°, 50° and 80° is an acute-angled triangle. Image caption, A scalene triangle with all angles less than 90° is an acute-angled triangle. A scalene ...

to build on students' knowledge of triangle and develop students' reasoning with properties of different classes of triangles to develop students' language related to the formal geometric names of ...

Properties of symmetry: - Students may notice symmetry in the isosceles and equilateral triangles and non-symmetry in the scalene triangles Informal recognition of these properties may be helpful in ...

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, right ...