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Mathematics and Life 67 Exterior angle property of a triangle

 Exterior angle property of a triangle


Background As shared in 300+ maths worksheets, the objective behind writing these notes, sharing these past worksheets handmade by me, in early 2000, is to revise core maths concepts - especially for the young mothers wanting to revise their maths basics. In that series, which is not in any pedagogical sequence, today we will explore the exterior angle property of triangles.

Exterior means outside the boundary. We have an external affairs ministry to handle matters outside the national boundaries. We use exterior paint for protecting the outer surface of our homes. 

Same way, the exterior angle of a triangle is an angle formed outside the triangle but between an extended side and another regular side. Some students misunderstand the concept and even treat the intersection of two sides forming an exterior angle. Which, in fact, is an interior and angle. 


Please note that in each of the figures shown in the sheet, the exterior angle has been taken in a different direction.

Extending different sides is extremely important for students to internalize that each of them is an exterior angle. 

Also, it worth noting here that even in 2005 or so, I used different variables each time to denote different angles, sides, vertices etc.

I am sure these all will help the teachers, tutors, young parents develop insight into the creativity development process.

Variants Adding colours, making children use protector (the D shaped angle measuring instrument) to varify the exterior angle property can add more value, skill to the understanding of the concept.

Dr Prakash Moghe

8085906062, 7489447223

drpnmoghe@gmail.com

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