I'm rather new towards Geometry, but here goes:
Given RP = TQ; and PS = QS, prove: RS = TS.
Right now all I really have is:
RP=TQ, PS=QS (Given)
and RP+PS = TQ+QS (Uh... Addition Prop of Equality?)
Then I'm kind of lost. I'm new to this whole idea of proofs, and I'm not sure where to look in my textbook... eh. Think someone could help me out?