Question

∠a≅∠b, ∠c≅∠b, ∠b≅∠c, ∠a≅∠c, m∠a = m∠c, def. of ≅ ∠s, symmetric prop., given, what is the missing justification? symmetric property, transitive property, reflexive property, substitution property

Explanation:

Step1: Identify given congruences

∠A ≅ ∠B, ∠C ≅ ∠B (given)

Step2: Apply symmetric property

∠B ≅ ∠C (symmetric property of congruence)

Step3: Determine missing justification

∠A ≅ ∠C requires transitive property (if a≅b and b≅c, then a≅c)

Answer:

B. transitive property