Slopes of Lines

1
Slopes of Lines

• Section 3-3

2
Definition of Slope

• The slope m of a line containing 2 points with
  coordinate (x1, y1) and (x2, y2) is given by the
  formula

3
Postulate 3-2 and 3-3

• 2 nonvertical lines have the same slope iff they
  are parallel.
• 2 nonvertical lines are perpendicular iff the
  product of their slopes is 1.

4
undefined slope
zero slope
positive slope
negative slope
5
Joke Time

• What do you call a hippo in a phone booth?
• stuck

6

• What would America be called if we all drove
  pink cars?
• A pink carnation