Presentation is loading. Please wait.

Presentation is loading. Please wait.

Warm Up 10.18.11 Week 1 1) If 3 + 4 = 7, then 7 = 3 + 4, State the postulate or theorem: 2) If 2x + 5 = 17, then 2x = 12. 3) If A and B are vertical angles,

Similar presentations


Presentation on theme: "Warm Up 10.18.11 Week 1 1) If 3 + 4 = 7, then 7 = 3 + 4, State the postulate or theorem: 2) If 2x + 5 = 17, then 2x = 12. 3) If A and B are vertical angles,"— Presentation transcript:

1 Warm Up Week 1 1) If = 7, then 7 = 3 + 4, State the postulate or theorem: 2) If 2x + 5 = 17, then 2x = 12. 3) If A and B are vertical angles, then A B.

2 Geometry 3.2 Day 1 I will prove results about perpendicular lines. Linear Pairs of Congruent Angles If two lines intersect to form a linear pair of congruent angles, then the lines are perpendicular Theorem 3.1 g hg h Ex

3 StepReason 1 2 Given: Prove: g h 1 2 Given: 1 and 2 are linear pairs Given 1 and 2 are linear pairs 1 2 m 1 + m 2 = 180º Definition of Linear Pairs m 1 = m 2 Definition of congruent angles m 1 + m 1 = 180º Substitution property of equality 2m 1 = 180º Simplify m 1 = 90º Division property of equality m 2 = 90º Substitution property of equality 1and 2 are right angles Definition of right angles g h Definition of perpendicular lines Ex 1 Prove T3.1

4 Perpendicular Adjacent Acute Angles If two sides of two adjacent acute angles are perpendicular, then the angles are complementary. Theorem º Ex

5 Four Right Angles If two lines are perpendicular, then they intersect to form four right angles. Theorem º Ex

6 Four Right Angles If two lines are perpendicular, then they intersect to form four right angles. Theorem º Ex

7 What can you conclude?: j k 2) 9 is a right angle 1) 7 and 8 are complementary Ex 2 j k ) 4)

8 Do: 1 Assignment: Handout - Section 3.2 B What is the value of x? ReviewA _______ is a line that intersects two or more coplanar lines. 65º x


Download ppt "Warm Up 10.18.11 Week 1 1) If 3 + 4 = 7, then 7 = 3 + 4, State the postulate or theorem: 2) If 2x + 5 = 17, then 2x = 12. 3) If A and B are vertical angles,"

Similar presentations


Ads by Google