1. What is a right triangle?
What is a right angle?
What is a parallelogram?

2. 14.) Identify and graph parallel and perpendicular lines.
1.) Identify linear functions and linear equations.
2.) Graph linear functions that represent real-world situations and give their domain and range.
3.) Find x- and y-intercepts and interpret their meanings in real-world situations.
 4.) Use x- and y-intercepts to graph lines.
5.) Find rates of change and slopes.
6.) Relate a constant rate of change to the slope of a line.
 7.) Find slope by using the slope formula.
 8.) Identify, write, and graph direct variation.
 9.) Write a linear equation in slope-intercept form.
 10.) Graph a line using slope-intercept form.
11.) 11.) Graph a line and write a linear equation using point-slope form.
13.) Write a linear equation given two points.
14.) Identify and graph parallel and perpendicular lines.
15.) Write equations to describe lines parallel or perpendicular to a given line.

3. Writing Linear Equations Given the Slope and a Point

4. Parallel and Perpendicular Lines
In a plane, nonvertical lines with the same slope are parallel. All vertical lines are parallel.
In a plane, two oblique lines are perpendicular if and only if (iff) the product of their slopes is -1. (In other words, their slopes are opposite reciprocals of each other.)
Vertical and horizontal lines are perpendicular.

8. Example:
Write the slope-intercept form of the equation of the line that passes through A(5, 9) and is parallel to the graph of y = 5x – 9.

9. Example:
Write the slope-intercept form of the equation of the line that passes through A(5, 9) and is perpendicular to the graph of y = 5x – 9.

10. Note: When writing equations of parallel lines, the only part of the given line we care about is the slope!!!!

11. Try:
Write the slope-intercept form of the eq. of the line that passes through the point (-2, 10) and is parallel to 2x + 5y + 4 = 0.

12. Try:
Write the slope-intercept form of the eq. of the line that passes through the point (-2, 10) and is perpendicular to 2x + 5y + 4 = 0.