Explore the properties of reflection by following these steps.

✓ 1. Press Reflect to perform a reflection of △ABC across the line.

✓ 2. Change the line of reflection by dragging point P to several different locations. Observe what happens to the lines that connect corresponding vertices.

✓ 3. Make a conjecture: What happens to m∠AJK, m∠BKJ, and m∠CLJ as you change the line of reflection?
The angles change.
The angles do not change.
The angles are always right angles.

✓ 4. Use the protractor to measure these angles:
m∠AJK = °
m∠BKJ = °
m∠CLJ = °

✓ 5. The line of reflection has been returned to its original position. Use the ruler to measure these two segments:
BK = units
KB' = units

✓ 6. Record the lengths of these segments:
AJ = units
JA' = units

✓ 7. Record the lengths of these segments:
CL = units
LC' = units

✓ 8. The exact lengths of the segments connecting corresponding vertices are:

BK  = 2.2 units    KB' = 2.2 units
AJ  = 5.6 units    JA' = 5.6 units
CL  = 3.8 units    LC' = 3.8 units

Which segments have equal lengths?

✓ 9. Change the position of the line of reflection. Does the line of reflection appear to be a perpendicular bisector of the segments that connect corresponding vertices?