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Methods of Proving Triangles Similar - Lesson 8-3

Today, we looked at how to show that two triangles are similar. This is very much like showing that two triangles are congruent (remember SSS, SAS, ASA, AAS?), with the exception that there are only three shortcuts (understanding that AAA~ and AA~ are the same due to the No Choice Theorem):

AA Similarity

SSS & SAS Similarity

So AA~, SSS~ and SAS~ work for proving triangle similarity. Now, remember the key thing with similarity is having congruent corresponding angles and proportional corresponding sides. Don't get this confused with proving congruence, where you're looking for congruent corresponding angles and congruent corresponding sides!!

Here was an example we did in class:

Example Proof


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Class Notes
Lesson 8-1
Lesson 8-2
Lesson 8-3
Lesson 8-4
Lesson 8-5
Test Topics
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