1. Slopes of Parallel and Perpendicular Lines

2. Different Forms of a Linear Equation  Standard Form  Slope-Intercept Form  Point-Slope Form  Standard Form  Slope-Intercept Form  Point-Slope Form Ax + By = C where A, B, & C are real numbers and A & B are not both zero y = mx + b where m is the slope and b is the y-intercept y - y 1 =m (x - x 1 ) where m is the slope and (x 1, y 1 ) is a point on the line

3. Slope  The slope of the nonvertical line through the points and is m = The slope of a vertical line is not defined. The slope of a horizontal line is zero.  The slope of the nonvertical line through the points and is m = The slope of a vertical line is not defined. The slope of a horizontal line is zero.

4. Slope of Parallel and Perpendicular lines  Two lines are parallel if and only if they have equal slopes.  Two lines are perpendicular if and only if the product of their slopes is -1.  Two lines are parallel if and only if they have equal slopes.  Two lines are perpendicular if and only if the product of their slopes is -1.

5. Examples  Find the slope of the line through the given points. a.(-4, 7) and (3, 7) b.(3, -1) and (3, 2) c.(1, -4) and (2, 5) d.(-2, 5) and (1, -1)  Find the slope of the line through the given points. a.(-4, 7) and (3, 7) b.(3, -1) and (3, 2) c.(1, -4) and (2, 5) d.(-2, 5) and (1, -1)

6. Examples  ANSWERS a. b. c. d.  ANSWERS a. b. c. d.