Question

the proof △abc ≅ △dcb that is shown. given: ∠a ≅ ∠d; cd||ab prove: △abc ≅ △dcb what is the missing reason in the proof? statement reason 1. ∠a ≅ ∠d 1. given 2. cd||ab 2. given 3. cb ≅ bc 3. refl. prop. 4. ∠abc ≅ ∠dcb 4. alt. int. ∠s are ≅ 5. △abc ≅ △dcb 5.? alt. ext. ∠s are ≅ asa aas corr. int. ∠s are ≅

Explanation:

We have two angles and a non - included side. Angle A is congruent to angle D (given), angle ABC is congruent to angle DCB (alternate interior angles are congruent), and side CB is common (reflexive property). The AAS (Angle - Angle - Side) congruence criterion states that if two angles and a non - included side of one triangle are congruent to two angles and the corresponding non - included side of another triangle, the two triangles are congruent.

Answer:

AAS