Difference between revisions of "Exterior angle property of a Triangle"
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=== Objectives === | === Objectives === | ||
| + | To show that exterior angle of a triangle is equal to the sum of its interior opposite angles. | ||
=== Estimated Time === | === Estimated Time === | ||
| + | 30 minutes | ||
=== Prerequisites/Instructions, prior preparations, if any === | === Prerequisites/Instructions, prior preparations, if any === | ||
| + | Knowledge about point, lines and angles, adjacent angles, alternate angles, corresponding angles, linear pair | ||
=== Materials/ Resources needed === | === Materials/ Resources needed === | ||
| − | Click here to [[:File:Exterior angle theorem of triangle.ggb|open]] the file | + | Digital : Click here to [[:File:Exterior angle theorem of triangle.ggb|open]] the file |
| + | |||
| + | Non-digital : Worksheet, pencil, ruler, compass, protractor | ||
=== Process (How to do the activity) === | === Process (How to do the activity) === | ||
| − | {{Geogebra|1=kxphjay3}} | + | {{Geogebra|1=kxphjay3}}'''Procedure:''' |
| + | # Draw triangle ABC | ||
| + | # Identify the angles of the triangle. | ||
| + | # What is the sum of the angles of a triangle? | ||
| + | # Extend one side, students should recognize the exterior angle formed. | ||
| + | # Measure the exterior angle of a triangle | ||
| + | # Identify interior opposite angles for the exterior angle of a triangle. Mark the angle in purple and green colour. | ||
| + | # Move the sliders and observe the changes. | ||
| + | # How are the two angles together related to the exterior angle? | ||
| + | # Do you notice any relation between the exterior angle and the interior angles | ||
=== Evaluation at the end of the activity === | === Evaluation at the end of the activity === | ||
| − | + | # What would be the measure of exterior angle for each vertex of an equilateral triangle? | |
| + | # Does an exterior angle of a triangle is smaller than either of its interior opposite angles? | ||
Go back to the page - [[KVS Triangles|click here]] | Go back to the page - [[KVS Triangles|click here]] | ||
Revision as of 22:55, 6 September 2020
Objectives
To show that exterior angle of a triangle is equal to the sum of its interior opposite angles.
Estimated Time
30 minutes
Prerequisites/Instructions, prior preparations, if any
Knowledge about point, lines and angles, adjacent angles, alternate angles, corresponding angles, linear pair
Materials/ Resources needed
Digital : Click here to open the file
Non-digital : Worksheet, pencil, ruler, compass, protractor
Process (How to do the activity)
Download this geogebra file from this link.
Procedure:
- Draw triangle ABC
- Identify the angles of the triangle.
- What is the sum of the angles of a triangle?
- Extend one side, students should recognize the exterior angle formed.
- Measure the exterior angle of a triangle
- Identify interior opposite angles for the exterior angle of a triangle. Mark the angle in purple and green colour.
- Move the sliders and observe the changes.
- How are the two angles together related to the exterior angle?
- Do you notice any relation between the exterior angle and the interior angles
Evaluation at the end of the activity
- What would be the measure of exterior angle for each vertex of an equilateral triangle?
- Does an exterior angle of a triangle is smaller than either of its interior opposite angles?
Go back to the page - click here