Lines BC and ED are parallel. They are intersected by transversal AE, in which point B lies between points and E. They are also intersected by transversal EC. Angle ABC measures 70 degrees. Angle CED measures 30 degrees. Given: line BC is parallel to line ED m∠ABC = 70° m∠CED = 30° Prove:m∠BEC = 40° Statement Justification line BC is parallel to line ED Given m∠ABC = 70° Given m∠CED = 30° Given m∠ABC = m∠BED Corresponding Angles Theorem m∠BEC + 30° = 70° Substitution Property of Equality m∠BEC = 40° Subtraction Property of Equality Which of the following accurately completes the missing statement and justification of the two-column proof? m∠BEC + m∠CED = m∠BED; Definition of a Linear Pair m∠ABC + m∠BEC = m∠BED; Angle Addition Postulate m∠ABC + m∠BEC = m∠BED; Definition of a Linear Pair m∠BEC + m∠CED = m∠BED; Angle Addition Postulate