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May 2006

1. ΔABC is congruent to ΔDEF.


2. Move the "drag" point or points A, B or C to view how they interact.

1. Congruence Theorems
2. Glencoe: On Line Quiz

1. Angle and 2 Sides
2. Side and 2 Angles
3. Three Sides
4. Three Angles

You see a ship sitting off shore. To determine its distance from shore, you do the following.
Select a point A on shore, then sight the angle to the ship from that point.
Walk to a new point B on shore and, again, sight the angle from that point to the ship. Reproduce these angles on the opposite side of the line AB. Continue the angle lines until they intersect.
a. How can you determine the distance to the ship in this way?
b. Why does this method work?