Below is a two-column proof incorrectly proving that the three angles of ΔPQR add up to 180°: StatementsReasons
∠QRY ≅ ∠PQRAlternate Interior Angles Theorem
Draw line ZY parallel to segment PQConstruction
m∠ZRP + m∠PRQ + m∠QRY = m∠ZRYAngle Addition Postulate
∠ZRP ≅ ∠RPQAlternate Interior Angles Theorem
m∠RPQ + m∠PRQ + m∠PQR = m∠ZRYSubstitution
m∠ZRY = 180°Definition of a Straight Angle
m∠RPQ + m∠PRQ + m∠PQR = 180°Substitution

Which statement will accurately correct the two-column proof?
The measure of angle ZRY equals 180° by definition of supplementary angles.
Angles QRY and PQR should be proven congruent after the construction of line ZY.
The three angles of ΔPQR equal 180° according to the Transitive Property of Equality.
Line ZY should be drawn parallel to segment QR.