SOLUTION: || AB, given AB = CD and AD = CB. Submit the entire proof to your instructor. Given: AB = CD AD = CB Prove: DC || AB I do not understand.

Algebra ->  Geometry-proofs -> SOLUTION: || AB, given AB = CD and AD = CB. Submit the entire proof to your instructor. Given: AB = CD AD = CB Prove: DC || AB I do not understand.      Log On


   

Question 938401: || AB, given AB = CD and AD = CB. Submit the entire proof to your instructor.
Given:
AB = CD
AD = CB
Prove:
DC || AB
I do not understand.
Answer by Edwin McCravy(20060) About Me  (Show Source):
You can put this solution on YOUR website!


Draw diagonal BD
AB = CD                                     given
AD = CB                                     given
BD = BD                                     identity
Triangle ABD congruent to triangle DCB      Side-Side-Side
Angle ABD = Angle CDB                       Corresponding parts of
                                               congruent triangles 
DC || AB                                    Since alternate interior
                                            angles ABD and CDB (when
                                            transversal BD cuts lines
                                            DC and AB), are equal, the
                                            lines cut are parallel

Edwin