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Addition & Subtraction Properties - Lesson 2-5

Today, we covered a number of new theorems regarding addition and subtraction of segments and angles.  We started by proving Theorem 8 (The Addition Property of Congruent Segments).

Theorem 8 Proof

We then proved Theorem 9 (The Addition Property of Congruent Angles).  Do you see the similarities here?  You should be starting to see these more and more...

Theorem 9 Proof

At this point, I showed you the following theorems (a second version of The Addition Property of Congruent Segments and The Addition Property of Congruent Angles).  You might want to take a shot at proving these.  It would be good practice for the chapter test (hint hint)!!

Theorems 10 - 11

And the follow two as well (two version of The Subtraction Property of Congruent Segments & Angles)!

Theorem 12 - The Subtraction Property of Congrunet Segments & Angles (Version 1)

Theorem 13 - The Subtraction Property of Congrunet Angles & Angles (Version 1)

You should be able to follow all the steps in these proofs and should be beginning to see some similarities between how they "flow."  Are you starting to recognize patterns?  Are you following each given as far as it goes?  Are you looking at the conclusion and working backwards?  Hopefully, you're starting to get the hang of things here, but if you're not, make sure to come to extra help!

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