Construction #2

To bisect an angle

Given an angle

scribe an arc centered at the vertex.

Let the points where this arc meets the arms of the angle be B and C. Scribe an arc centered at B and an arc centered at C with the same radii.

Let the point where these arcs meet be D. Draw AD.

AD is the bisector of the angle at A.

Theorem:

Given:

• AB = AC
• BD = CD

To prove:

Angle BAD = angle CAD

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