1. Constructing Perpendicular Bisectors
During this lesson, we will:
Construct the perpendicular bisector of a segment
Determine properties of perpendicular bisectors

2. Daily Warm-Up Quiz
A point which divides a segment into two congruent segments is a(n) _____.
2. If M is the midpoint of AY, then
a. AM = MY c. Both a and b.
b. AM + MY = AY d. Neither a nor b.

3. I wonder how many segment bisectors I can draw through the midpoint?
Before we start:
a line, segment, or ray which intersects a segment at its midpoint
Segment Bisector: ________________ ______________________________
I wonder how many segment bisectors I can draw through the midpoint?

4. Paper-Folding a Perpendicular Bisector
STEP 1 Draw a segment on paper. Label it OE. STEP 2 Fold your paper so that the endpoints O and E overlap with one another. Draw a line along the fold. STEP 3 Name the point of intersection M. Step 4 Measure the four angles which are formed, and segments ON and NE.

5. Definition: Perpendicular Bisector
a line, ray, or segment that a. intersects a segment at its midpoint and b. forms right angles (90)
Add each definition to your illustrated glossary!

6. Construction: Perpendicular Bisector, Given a Line Segment
Absent from class? Click HERE* for step-by-step construction tips.
Please note: This construction example relies upon your first constructing a line segment.