the theorems and postulates used in the proof.
http://wiki.answers.com/Q/What_do_you_use_as_reaso...

In a twocolumn table of a geometric proof, the statements are
http://www.chacha.com/question/whatisusedtosup...

We use proven theorems, axioms, & definitions to support a geometric proof.
http://www.kgbanswers.com/whatisusedtosupport...

I know! I hate these so much! But from what i understand 3,2,1 are congruent, and ACB is made up of angles 2 and 3. 1) <ACB is rt. angle reason: given. 2) <ACB =90 degrees reason
http://answers.yahoo.com/question/index?qid=200910...
