Parallel and Perpendicular Lines

1
Parallel and Perpendicular Lines

• http//www.wtamu.edu/academic/anns/mps/math/mathla
  b/col_algebra/col_alg_tut28_parpen.htm

2

 

3
 

4
Geometric Interpretation of Slope
Line Slope Example
2-1-5
5
 
 

6
Examples

• Find the slope of the line that passes through
  the points (-2, 3) and (4, -1).

7
Examples

• Find the slope of the line that passes through
  the points (7, 4) and (7, -1).

8
Equations of a Line
6x 5y 45


2-1-4
9
Given m 3 (-5, 4)
We write y - 4 3(x 5)
10
y 45
x 10
11
Writing the equation of a line

12
 

 

13
You Try

• Write an equation for the line in point/slope
  form and slope/intercept form that has slope ½
  and passes through (4, 6).
• Write you answer in slope intercept form.

14
Parallel and Perpendicular Lines
15
 

16
 
   
17
Examples

• Find the equation of a line that is parallel to y
  2x 3 and passes through the point (4, 3).
  Write you answer in slope intercept form.

18
Examples

• Find the equation of a line that is perpendicular
  to y 2x 3 and passes through the point (4,
  3). Write you answer in slope intercept form.

19
Examples

• Find the equation of a line that is parallel to y
  ½x 9 and passes through the point (3, -1).
  Write you answer in slope intercept form.

20
Examples

• Find the equation of a line that is perpendicular
  to y -¼ x 3 and passes through the point (0,
  -3). Write you answer in slope intercept form.

21
Examples

• Find the equation of a line that is parallel to y
  (-3/4)x 3 and passes through the point (1,
  9). Write you answer in slope intercept form.

22
Example

• Write the equation of the line that is
• a) parallel to the equation x 4 and passes
  through the point (-3, 19).
• b) perpendicular to the equation x 4 and passes
  through the point (-3, 19).

23
Assignment

• 3.6-3.7 Worksheet
• Chapter Review
• Chapter 3 Test Friday