Answer:
ASA rule.
Step-by-step explanation:
See the diagram with the problem.
Given that Δ ABC and Δ ABD are congruent i.e. Δ ABC ≅ Δ ABD.
Now, we have to select the rule by which we can say that Δ ABC and Δ ABD are congruent.
Given in the figure that between Δ ABC and Δ ABD,
(i) ∠ CAB = ∠ BAD
(ii) AB is the common side, and
(iii) ∠ ABC = ∠ ABD
Therefore, by Angle-Side-Angle i.e. ASA rule we can say that Δ ABC ≅ Δ ABD.
Hence, option 2 is correct. (Answer)
