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Overlapping Triangles - Lesson 3-5

We didn't really learn much new today...rather, we just applied what we've already learned to triangles that are overlapping and therefore sharing some part(s).  An example is below:

Example of Overlapping Triangles proof


We also went over the following example...can it be proved?

Overlapping Triangles Example 1

As we saw, we only have SSA here, which we know doesn't work (unless the triangle is a right triangle!).  Clearly, in the diagram below, the triangles aren't congruent, even though the same parts are congruent!.  Wouldn't it be nice if you had Sketchpad and a SmartBoard on your tests so that you could play with the figures like we can in class?!?

Overlapping Triangles Example 1 Answer


Before going over homework, we also went through the following example...does it work?

Overlapping Triangles Example 2

As we saw, it does...I've pulled out the two triangles (in red and green below) because it sometimes helps to look at them in this way...

Overlapping Triangles Example 2 Answer


Make sure to do all your homework as these things really take a lot of practice to get used to "seeing" the correct triangles...

Other Links
Class Notes
Lesson 3-1
Lesson 3-2
Lesson 3-3
Lesson 3-4
Quiz Topics
Lesson 3-5
Lesson 3-6
Lesson 3-7
Lesson 3-8
Test Topics
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