3rd Angle Of A Triangle Proof

This lesson is part of the following series:

Basic Beginning Algebra and Geometry Series (30 lessons, $24.75)
Geometry Made Easier (19 lessons, $12.87)

It's fairly obvious that if two angles of one triangle are congruent to two angles of another triangle, then the third angles are congruent. However, how to write the proof may not be so obvious. For that matter, how to write ANY proof may not be so obvious!

That is probably the understatement of the world! Most students find proofs to be very difficult. This video "illustrates" a proof but doesn't really teach you how to write a proof. That will need a video all it's own! Coming soon.

For now, the most important part of this video is to get the concept of the 3rd angle...and, thank goodness, that IS very easy to get.

Learn this theorem. Do not worry if you cannot write the proof as I did. Try to follow me though. At this stage, being able to just follow my proof is enough. The concept is important to know. The proof...just follow me for now.

Welcome! I'm so glad you are here! Math help is here for you.

I believe that using these Algebra and Geometry videos will help you understand math.

Some students try very hard and still struggle to pass math. They start off strong but things suddenly begin to fall apart. That happens as soon as the student becomes lost. Teenagers who find themselves in this position often let it "get away from them" before they seek help. Because Algebra is a class of stepping stones, it rarely gets better without help.

I urge you to seek help from your child's teacher first. Always. These Algebra and Geometry videos can help too. You can watch the topic you need over and over. Repetition is...

Proofs-Yuk

09/23/2011

~ milly91

I seriously can't do proofs. But this is good and I am getting better at it. I wish you lived next door to me!

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