Prentice Hall Geometry

Essential Understanding There is a special relationship between the points on the bisector of an angle and the sides of the angle.

The distance from a point to a line is the length of the perpendicular segment from the point to the line. This distance is also the length of the shortest segment from the point to the line. You will prove this in Lesson 5-6. In the figure below, the distances from A to l and from B to l are represented by the red segments.

Horizontal line l has point A above and point B below, with vertical line segments from each meet line l at right angles.

In the diagram, eh d vector  is the bisector of angle c eh b .  If you measure the lengths of the perpendicular segments from D to the two sides of the angle, you will find that the lengths are equal. Point D is equidistant from the sides of the angle.

Angle CAB has ray AD creating equal angles CAD and DAB. Segments measuring 3 extend from D on ray AD and meet rays AC and AB at right angles.


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Table of Contents

Prentice Hall Geometry Chapter 1 Tools of Geometry Chapter 2 Reasoning and Proof Chapter 3 Parallel and Perpendicular Lines Chapter 4 Congruent Triangles Chapter 5 Relationships Within Triangles Chapter 6 Polygons and Quadrilaterals Chapter 7 Similarity Chapter 8 Right Triangles and Trigonometry Chapter 9 Transformations Chapter 10 Area Chapter 11 Surface Area and Volume Chapter 12 Circles Skills Handbook Reference Visual Glossary Selected Answers Index Acknowledgments