Complete the paragraph proof of the Third Angles Theorem Then write a two column proof Given ZA ZD ZB LE Prove C LF A C 2 E by the definition of congruent angles and then Because ZA ZD and LB LE m A m B m2C 180 and mZD m E mZF 180 by the by the Transitive Property of Equality Using the Substitution Property of Equality twice m A m2B m C mZA m B mZF By the m C m F and ZC ZF by the definition of congruent angles