Types of triangles based on angles

Acute triangle, obtuse triangle and right triangle are different types of triangles that are formed with different measures of angles.

Objectives
Recognize the triangles based on the measures of the sides

Estimated Time
20 minutes

Prerequisites/Instructions, prior preparations, if any
Prior knowledge of point, lines, angles, elements of triangle

Materials/ Resources needed

 * Digital : Computer, geogebra application, projector.
 * Non digital : Worksheet and pencil.
 * Geogebra files : “Types of triangle by angle.ggb”

Process (How to do the activity)
Evaluation at the end of the activity
 * Identify the angle types in the triangle.
 * Can the angles in the triangle be of different type – obtuse or right  angle.
 * Establish the types of triangles based on the types of angles that form the  triangle – when  all angles are acute angles,  when  one  of the angle is a right  angle and when  one of the angle is   obtuse angle.
 * Is it possible to have a triangle with two right angle or two obtuse  angle. Why or why not?
 * What kind of a triangle is formed when all the angles are equal? For  what measure of the angle such a triangle is formed?
 * Can a triangle be formed with a reflex angle.
 * Measure the angles for different triangle, recognize the types of angles  and conclude the type of triangle.
 * Are children able to recognize the types of triangles based on the angles in a triangle.