Presentation on theme: "Angles and Triangles p.551 D E F"— Presentation transcript:
1. . 9.5 Angles and Triangles p.551 D E F Name the angle in five different ways.Angle DEF, angle FED,DEF, FED, or E
2. . P R Q Name the angle in five different ways. Angle PQR, angle RQP, PQR, RQP, or Q
3. . . Classifying Angles p.553 Right angle: An angle whose measure is 90o.Straight angle:An angle whose measure is 180o....CDE
4Acute angle:An angle whose measure is greaterthan 0o and less than 90o.Obtuse angle:An angle whose measure isgreater than 90o and less than 180o.
5Classify the angles as right, straight, acute or obtuse. Right angle...Straight angleCDEObtuse AngleAcute angle
6Complementary Angles p. 554 Two angles are complementary if the sum of their measures is 90o. Each angle is called a complement of the other.Find the measure of a complement of the angle.15o45o188.8.131.52o75o45o18o
7Supplementary Angles p. 555 Two angles are supplementary if the sum of their measures is 180o. Each angle is called a supplement of the other.Find the supplement of the angle given.1.38oo3. 90o142o23o90o
8Triangles p. 555A triangle is a polygon made up of three segments, or sides. A triangle with vertices A, B, and C can be named ABC.ICFABEDGH
9Types of Triangles p. 556 All sides are the same length. Equilateral triangle -Isosceles triangle –Scalene triangle –Two or more sides are the same length.All sides are of different lengths.
10Types of Triangles p. 556 Right triangle – Obtuse triangle – Acute triangle –One angle is a right angle.One angle is an obtuse angle.All three angles are acute.
11Sum of the Angle Measures of a Triangle In any triangle ABC, the sum of the measuresof the angles is 180o.Find the measure of angle A.Bx + 65o + 24o = 180o65ox + 89o = 180ox24ox = 180o – 89oCAx = 91o