![This proves how the sum of the interiror angles of a triangle always equal to 180 degrees :) | Triangle angles, Equality, Quadrilaterals This proves how the sum of the interiror angles of a triangle always equal to 180 degrees :) | Triangle angles, Equality, Quadrilaterals](https://i.pinimg.com/originals/66/68/4b/66684b47dab98e16be8efd09d46ff75a.png)
This proves how the sum of the interiror angles of a triangle always equal to 180 degrees :) | Triangle angles, Equality, Quadrilaterals
Why are the sums of the exterior angles of a triangle equal to the sum of the two opposite interior angles? - Quora
![geometry - What's a proof that the angles of a triangle add up to 180°? - Mathematics Stack Exchange geometry - What's a proof that the angles of a triangle add up to 180°? - Mathematics Stack Exchange](https://i.stack.imgur.com/8UuqW.png)
geometry - What's a proof that the angles of a triangle add up to 180°? - Mathematics Stack Exchange
![A triangle has sides A, B, and C. Sides A and B have lengths of 2 and 6, respectively. The angle between A and C is (pi)/4 and the angle between B A triangle has sides A, B, and C. Sides A and B have lengths of 2 and 6, respectively. The angle between A and C is (pi)/4 and the angle between B](https://useruploads.socratic.org/ubxpzpuYStCublxo2JB9_equal%20angle%20equal%20side.jpg)