How to Construct a Bisector of a Given Angle

Step-by-Step Guide

1. 1

   Step 1: Measure the angle.

   Place the origin hole of the compass on the angle’s vertex, lining up the base line with one of the angle’s rays.
   
   Look at the degree mark where the other ray falls.
   
   This will tell you the degree measurement of the angle.
   
   For example, you might measure an angle that is 160 degrees wide.
   
   Remember that protractors have two sets of numbers.
   
   To know which set of numbers to look at, think about the size of the angle.
   
   Obtuse angles are greater than 90 degrees, and acute angles are less than 90 degrees.
2. 2

   Step 2: Divide the number of degrees in half.

   An angle bisector divides an angle into two equal parts.So, to find where the angle bisector lays, divide the number of degrees in the angle by
   2.For example, if the angle is 160 degrees, you would calculate 1602=80{\displaystyle {\frac {160}{2}}=80}.
   
   So, the angle bisector is at the 80-degree mark of the angle. , Again, line up the origin hole with the angle’s vertex, and line up the base line with one of the rays.
   
   Find the halfway point using the protractor.
   
   Mark this point in the angle’s interior.
   
   For example, if the bisector of a 160-degree angle lies at the 80-degree point, you would find the 80-degree mark on the protractor and and draw a point at this location in the angle’s interior. , Use the straightedge of the protractor to connect the vertex to the halfway point of the angle.
   
   The line you draw is the angle’s bisector.
3. 3

   Step 3: Draw a point marking the measurement of the bisector.

4. 4

   Step 4: Draw a line from the vertex to the point.

Detailed Guide

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