1. 1.6 Lines

4. y x

5. L y x

7. Draw a graph of a line passing through
the point (1,4) and having a slope -3/2.

8. (1, 4) -3
(3, 1) 2

9. Vertical Line

10. Graph the equation : x = 2

11. y
x = 2 x

12. ( ) Point-Slope Equation An equation of a nonvertical line of slope xy 1 , m
that passes through the point is

15. (0, 3)
(1, 1)

16. Equation of a Horizontal Line
A horizontal line is given by an equation of the form
y=b
Where b is the y-intercept.

17. Find the equation and sketch a graph of a
horizontal line passing through (1,4).

18. y
y = 4 x

19. Slope-Intercept form of an Equation of a Line
An equation of a line L with slope m and y-intercept b is
y=mx+b

20. Th equation of a line L is in general form
when it is written:
Where A, B, and C are three real numbers and
A and B are not both 0.

21. Criterion for Parallel Lines
Two nonvertical lines are parallel if and
only if their slopes are equal and they have
different y-intercepts.

22. Two lines are said to be perpendicular if they intersect at a right (90o) angle.

23. Criterion for Perpendicular Lines
Two nonvertical lines are perpendicular if
and only if the product of their slopes is -1.
The corresponding slopes m1 and m2 have the following relationship: