1. Perpendicular Lines
SECTION 2.5

2. Definition
Perpendicular lines are two lines that intersect to form right angles (90o).

3. l n

4. Perpendicular THEOREM
Perpendicular lines form adjacent angles.

5. 2x + 10 + x – 7 = 90o 3x + 3 = 90o 3x = 87o x = 29o 2x + 10 x – 7
DRAW THIS FIRST
2x + 10

6. 9x – x = 180o
11x – 18 = 180o
11x = 198o
x = 18o
DRAW THIS FIRST
9x – 18 2x

7. Name the theorem or state the definition that justifies the statement below.
Definition of ⏊
⏊ Theorem
⏊ Theorem

8. Now work!
Written Exercises
Page 58-59
#3 – 12, 18 – 25

9. PRACTICE PROBLEMS
PAGE 57
Classroom Exercises
#2-11
Line Song