Given an angle formed by two lines with a common vertex, this page shows how to construct another angle from it that has the same angle measure using a compass and straightedge or ruler. It works by creating two congruent triangles. A proof is shown below. A Euclidean construction
Constructions Mathematics for Students
How can we divide a right angle into five equal parts with ruler and compass? - Quora
Constructing 30deg Angle, PDF, Triangle
Constructing Angle Bisectors - Construction using a compass, proof of angle bisector, examples.
Copies of Line Segments and Angles ( Read ), Geometry
Constructions How to Copy An Angle
Geometric constructions: angle bisector (video)
How to Construct Congruent Angles, Geometry
Two shapes you cannot construct with a straight edge and compass, by Keith McNulty