Angles which lie between zero degrees to ninety degree are termed as acute an angle, which is it lies between 00 and 900. On the other hand, angles which lie between ninety degree and one hundred eighty degree are termed as obtuse angles that is it lies between 900 and 1800 and reflex angle is defined as an angle which lies between one hundred eighty degree and three hundred sixty degrees, that is it lies between 1800 and 3600 or we can say that any angle which is more than 1800 and less than 3600 is known as reflex angle. Now question arises how to bisect a reflex angle.
Since we know that on drawing any Right Angle or acute angle, a reflex angle is automatically created. Thus, for bisecting any reflex angle we need to use compass and scale. Suppose an acute angle ABC constituting two rays AB and BC. Thus, other side of angle will form a reflex angle and for bisecting this reflex angle, first we need to draw an arc from Ray AB to other side of acute angle that is towards the side of reflex angle. Then on same side draw another arc cutting or intersecting the previous arc. Point where both arcs meet or cut each other, mark that point as 'S' and now join point 'B' and point 'S'. Thus this ray BS will be the bisector of reflex angle and it is termed as Angle Bisector of this reflex angle.