Section 14 1 Angles Formed by Intersecting Lines
Section 14. 1: Angles Formed by Intersecting Lines 1
Objective: By following instructions, students will be able to: 1. Find the measures of angles formed by intersecting lines. 2
DEF: complementary angles – two angles whose sum of their measures is 90 degrees. DEF: supplementary angles – two angles whose sum of their measures is 180 degrees. COMPLEMENTARY ANGLES SUPPLEMENTARY ANGLES (adjacent and nonadjacent) 3
Def: linear pair – two adjacent angles whose non common sides are opposite rays. 4
Def: vertical angles– two angles whose sides form two pairs of opposite rays. • Angles are congruent 5
explain 1 Cross braces help keep the deck posts straight. Find the measure of each angle. a) b) and 6
Your-Turn #1 The measures of two vertical angles are given by the expressions (x + 3)° and (2 x - 7)°. Find the value of x. What is the measure of each angle? 7
DEF: complementary angles – two angles whose sum of their measures is 90 degrees. DEF: supplementary angles – two angles whose sum of their measures is 180 degrees. COMPLEMENTARY ANGLES SUPPLEMENTARY ANGLES (adjacent and nonadjacent) 8
explain 2 Use the diagram below to find the missing angle measures. Explain your reasoning. a) Find the measures of and . b) Find the measures of and . 9
Revisit Objective: Did we… 1. Find the measures of angles formed by intersecting lines? 10
HW: Sec 14. 1 pg 508 #s 1 -12 11
- Slides: 11