State exterior angle theorem

Exterior angle theorem: If a side of a triangle is produced; the exterior angle so formed is equal to the sum of the two interior opposite angles.

THEOREM (Exterior Angle Property of a Triangle): If a side of a triangle is produced the exterior angle so formed is equal to the sum of two interior opposite angles.

Theorem 6.8 : If a side of a triangle is produced, then the exterior angle so formed is equal to the sum of the two interior opposite angles.

The sum of the exterior angles of a hexagon is

Can the exterior angle of a triangle be a straight angle?

In a regular convex polygon, each interior angle in not more than each exterior angle is not more than each exterior angle. How many such polygons are possible ?

The ratio between the interior angle and the exterior angle of a regular polygon is 2: 1. Find : (i) each exterior angle of the polygon. (ii) number of sides in the polygon.

Calculate the number of sides of a regular polygon, if (i) its interior angle is five times its exterior angle. (ii) the ratio between its exterior angle and interior angle is 2:7. (iii) its exterior angle exceeds its interior angle by 60^@ .