You are given an isosceles triangle ABC with sides AB = BC. Points D and E are located on the base

You are given an isosceles triangle ABC with sides AB = BC. Points D and E are located on the base so that AD = EC, ∡CEB = 151 °. Define EDB. ∡EDB =

Answer: ∡EDB = 151 °
Solution: consider the resulting triangles BAD and CBE,
since sides AB = BC (by condition)
and sides AD = EC (by condition),
a ∡ BAC = ∡ BCA (property of an isosceles triangle – the angles at the base are equal (in triangle ABC, the base is the AC side)),
then by the first sign of equality of triangles: triangle BAD = triangle CBE,
respectively, in equal triangles opposite to respectively equal sides there are equal angles, and hence
∡CEB = ∡EDB = 151 °