Introduction
Notice how the roads intersect at right angles in the image below.
This means the lines are perpendicular.
- Visit GeoGebra PBT (Part 2) on perpendicular bisectors.
- Once you have completed the GeoGebra, go to the 5.02 Perpendicular Bisector Discussion and answer the following question.
- What do you notice about the point on the perpendicular bisector?
- Move the point, what do you notice?
- Then, read another student's answer and critique it. Did they notice something you did not?
- Can you add additional information to their answer?
Be sure to look at the 5.02 Perpendicular Biesector Discussion Scoring Guide.
Following successful completion of this lesson, students will be able to...
- Prove points on a perpendicular bisector is equal lengths from the endpoints of the segment
- Construct perpendicular bisectors and lines.
Essential Questions
- How can I prove that two lines are parallel or perpendicular using angle measurements?
- How can I use theorems and postulates about lines and angles to solve problems?
Enduring Understandings
- Perpendicular lines can be proven by the relationship of their slopes.
- If we know the measure of one angle formed when a pair of parallel lines is cut by a transversal, then we can find the measures of the other angles.
- You can use the measure of angles to prove that lines are parallel.
- If we know the measure of one angle formed when a pair of parallel lines is cut by a transversal, then we can find the measures of the other angles.
- You can use theorems and postulates about lines and angls to find unkonwn measurements.
The above objectives correspond with the Alabama Course of Study: Geometry with Data Analysis standards: 29, 29a, 29b, 30 and 31a.