Triangle ABC is congruent to triangle DEF.
In triangle ABC, side AB measures 9, side BC measures 3x+18, and side CA measures 7.
In triangle DEF, side DE measures 9, side EF measures 2x+26, and side FD measures 7.
What equation would help you to solve for the side length of BC and EF?
(Actual question in an on-line geometry course.)
What would you do to fix this question?