Angle Bisector in Triangles

What is a line segment or ray drawn from a vertex that divides the angle into two congruent angles?

• Median of a Triangle

• Altitude of a Triangle

• Perpendicular Bisector of a side of a Triangle

• Angle Bisector

• Midpoint of a Line Segment

A ray that divides an angle into two congruent angles.

• Angle Bisector

• Segment Bisector

• Midpoint

• Sunshine

What does an angle bisector do?

• Makes two 90 degree angles

• splits a 90 degree angle in half

• splits an angle in half

• splits 2 sides in half

Find BD.

• BD = 20

• BD = 2

• BD = 4

• BD = 10

Mix and Match

• CPCTC

• Side Angle Side

• Definition of Angle Bisector

• Given

• Reflexive Property

What is reason 2?

• 
• 
• 
• 

What is the "statement" for step 2 of the proof?

• ∆BAC≅∆DAC

• BC=DC

• ∡B≅∡D

• ∡BAC≅∡DAC

If DA bisects IE, then

• ID=ED

• IA=EA

• <IDA=<EDA

• <IAD and <EAD are right angles

What is reason 1?

• 
• 
• 
• 

What is reason 3?

• 
• 
• 
•