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Mathematics equilateral triangle in eighth grade
Option d

△ABC and△△△ CDE are equilateral triangles.

Then ∠1+∠ 2 = ∠ 2+∠ 3 = ∠ ced = ∠ CDE = 60.

So ∠ 1=∠3, ∠ CEA =180-∠ ced =120.

Ac = BC,ce = CD。

So △ ace △ BCD

So ∠ CDB = ∠ CEA = 120.

So ∠ EDB = ∠ CDB-∠ CDE = 60.

So AEB = EBD+EDB = 38+60 = 98.

The thinking of solving problems and the degree of finding angles are generally related to similarity, congruence, parallelism, outer angle, inner angle and their relationships ~ There are two equilateral triangles with vertices, and congruence comes to mind first ~ I hope it can help you ~