1.4 Angle Measure Objectives: Measure and classify angles. Identify and use congruent angles and the bisector of an angle.

ray Part of a line with one endpoint AB AB

angle Formed by two non- collinear rays that have a common endpoint Named <ABC, <1, or <CBA Point D is in interior Point E is in exterior A B C 1 vertex D E

Use the figure to name the vertex of each angle <1  vertex is P <2  vertex is P <3  vertex is O <4  vertex is O <5  vertex is... P M N O R Q

Use the figure to name the sides of each angle <1  PM and PN <2  PN and PO <3  OR and OQ <4  OM and OQ <5  sides are... P M N O R Q S

Use the figure to give another name for each angle <1  <MPN <NPO  <2 <3  <ROQ <QON  <4 <5  ??... P M N O R Q S

Classify angles Acute = less than 90º Right = 90 º Obtuse = more than 90 º Name every acute angle: <1, <2, <5, <MPO Name every right angle: <3, <4, <MOP, <POR Name every obtuse angle: <MNP P M N O R Q S

Bisect Divides an angle into 2 congruent (equal) angles BD bisects <ABC <1  <2 A B C D 1 2

ED bisects <AEG. M<AED = 3p + 2 and m<DEG = 5p – 38. Find the measure of <AED. 3p + 2 = 5p – 38 -3p 2 = 2p – = 2p 20 = p m<AED = 3(20) + 2 = 62º A D E G

Assn: pp #9-37