Properties of Equality for Real Numbers

[rubyred]

How do I remember all of the properties to use when I do proof's in geometry?
I get subtraction, substitution mixed up.
I also get Symmetric and Transtive mixed up!
Also usually when I solve a proof I get mixed up and screw the whole problem up!
Lost in Proofs! Please Help

 

[Denis]

Post an actual problem. Show where you're stuck.