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KatieMO
Help on angles and congruency??
if AB = CD, then we can prove triangles are congruent by ASA. rest all options are useless. the first option is redundant as it can be deduced by the given info that AB || CD. other two options make no sense. only the last option AB = CD works.
isn't that given though??
its not given. look closely, its give AB || CD. it doesnt say if AB = CD or not.
Ohh. ok. baha wooww. thanks ya!!
well i see u r correct, AB = CD can also be deduced by the given statement that \(\triangle ABD \cong \triangle CDB.\) still last option is right, as AB = CD is deduced by using the corresponding parts rule.