1. Topic: Slopes of Lines
Section: 3-3
Concept

2. A. Find the slope of the line.
Find the Slope of a Line
A. Find the slope of the line.
Substitute (–3, 7) for (x1, y1) and (–1, –1) for (x2, y2).
Example 1

3. B. Find the slope of the line.
Find the Slope of a Line
B. Find the slope of the line.
Substitute (0, 4) for (x1, y1) and (0, –3) for (x2, y2).
Slope formula
Substitution
Simplify.
Answer: The slope is undefined.
Example 1

4. C. Find the slope of the line.
Find the Slope of a Line
C. Find the slope of the line.
Substitute (–2, –5) for (x1, y1) and (6, 2) for (x2, y2).
Slope formula
Substitution
Simplify.
Answer:
Example 1

5. D. Find the slope of the line.
Find the Slope of a Line
D. Find the slope of the line.
Substitute (–2, –1) for (x1, y1) and (6, –1) for (x2, y2).
Slope formula
Substitution
Simplify.
Answer: 0
Example 1

6. Concept

7. Concept

8. Determine Line Relationships
Determine whether and are parallel, perpendicular, or neither for F(1, –3), G(–2, –1), H(5, 0), and J(6, 3).
Example 3

9. Determine whether AB and CD are parallel, perpendicular, or neither for A(–2, –1), B(4, 5), C(6, 1), and D(9, –2)
A. parallel
B. perpendicular
C. neither
Example 3

10. Use Slope to Graph a Line
Graph the line that contains Q(5, 1) and is parallel to MN with M(–2, 4) and N(2, 1).
Example 4

11. Graph the line that contains R(2, –1) and is parallel to OP with O(1, 6) and P(–3, 1).
A. B.
C. D. none of these
Example 4