Education Technology


Angle Bisectors in a Triangle

Activity Overview

In this activity, students will explore the relationships between an angle bisector and segments in a triangle. They will determine the distances from an angle bisector to the sides of the bisected angle. In a triangle, proportional relationships occur when an angle bisector divides the opposite side into two parts.

Key Steps

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    First, students will investigate the Angle Bisector Theorem. Students should see that the angle bisector is equidistant from both sides of the angle.

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    Next, students will explore an angle bisector in a triangle. Students should see the relationships between the sides of the triangle and the bisector.

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    As an extension, students will explore the incenter of a triangle.