ABC and DBC are two isosceles triangles on the same base BC (see Fig). Show that ∠ABD = ∠ACD.
ABC and DBC are two isosceles triangles on the same base BC (see Fig). Show that ∠ABD = ∠ACD.
Solution and Explanation
Let us join AD.
In ∆ABD and ∆ACD,
AB = AC (Given)
BD = CD (Given)
AD = AD (Common side)
∠∆ABD ≅ ∠∆ACD (By SSS congruence rule)
∠ABD = ∠ACD (By CPCT)
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