How do you write a two column proof that has triangle AbC is equiangular for the given and EF is parallel to AC and prove triangle EFB is equiangular?

To write a two-column proof demonstrating that triangle EFB is equiangular given that triangle ABC is equiangular and line EF is parallel to AC, first list the given information in the left column. In the right column, write the corresponding statements: since EF is parallel to AC, by the Corresponding Angles Postulate, angle EFB is equal to angle ABC, and angle AEF is equal to angle CAB. Finally, since triangle ABC is equiangular, the third angle EBF will also be equal to angle ACB, proving triangle EFB is equiangular.