Adjacent angles

From Karnataka Open Educational Resources

Adjacent angles are two angles that have a common vertex and a common side. The vertex of an angle is the endpoint of the rays that form the sides of the angle.  


Introduce children to concept of adjacent angles

Estimated Time

20 minutes

Prerequisites/Instructions, prior preparations, if any

Prior knowledge of point, lines, angles

Materials/ Resources needed

  • Digital : Computer, geogebra application, projector.
  • Non digital : Worksheet and pencil.
  • Geogebra files : Adjacent angles.ggb

Download this geogebra file from this link.

Process (How to do the activity)

  • Prior hands on activity (optional – children can use news paper strips to form angles and place them together and notice the resulting angle formed).
  • Change the measure of the angles – angle1 and angle 2 using the slider
  • If the two angles are place next to each other , what will be formed
  • Use the slider to place the angles next to each other
  • What is the resulting angle formed due to the two angles
  • What is the measure of the angle formed when the two are placed to each other
  • Is there any other way to make the two angles adjacent
  • Record the values of the two angles and their sum in the worksheet
Sl No. Angle ABC Angle DEF Angle ABC + Angle DEF Angle O Is the sum of two angles greater than Angle O

Evaluation at the end of the activity