Bisecting an Angle
How to Bisect an Angle
What You Start With
Shown above is an angle that we are going to bisect into two equal parts.
Proof:
- AB is congruent to AC because they were both drawn with the same compass radius.
- BD and CD are congruent because they were drawn with the same compass radius.
- Therefore Triangles ABD and ACD are congruent becasure they have three sides in common. (AD is common to both triangles.)
- Angles BAD and CAD are congruent because they are the corresponding sides of congruent triangles.
- Hence the line AD bisects the angle BAC into two equal angles.
Bisecting an Angle Interactive