1. Precalculus Section 1.2 Find and apply the slope of a line
The slope of a line passing through the points (x1,y1) and (x2,y2) is given by: m = ∆y ∆x m = (y2 - y1) (x2 – x1)

2. examples
Find the slope of the line containing the points (4,-3) and (8,5)
Find the slope of the line containing the points (7,2) and (6,2)
Find the slope of the line containing the points (9,-1) and (9,8)

3. Slopes of lines

4. Linear equation in slope intercept form y = mx + b m is slope b is y intercept
Find the slope and y intercept.
y = ⅘x – 6
3x – 5y = 7

5. Parallel lines have the same slope
Parallel lines have the same slope. Perpendicular lines have opposite reciprocal slopes.
Determine whether the lines are parallel, perpendicular, or neither.
2x + 5y = y = 5/2 x + 3
Find the value of k if the line joining (2,k) and (4,5) and the line y = 3x +1 are perpendicular.

6. Assignment
Page 11
Problems 2 – 24 even (26ec)