Sum of interior angles of the triangle

A closed figure joined by three line segments is called a triangle. It has 3 vertices, 3 sides, 3 angles. Sum of interior angles is 180 degrees If move the vertex B and C then angles are change but their sum is 180 degrees.

A closed figure joined by three line segments is called a triangle. It has 3 vertices, 3 sides, 3 angles. Sum of interior angles is 180 degrees. If move the vertex B and C then angles are change but their sum is 180 degrees.