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Mathematics and geometry problems in the first volume of the second day of junior high school
Analysis: First, we can get the degree of ∠ABC according to the triangle interior angle theorem, then we can get the degree of ∠EBD according to the properties of the angle bisector, and then we can get the degrees of ∠EDB and ∠BED according to the properties of parallel lines and the triangle interior angle theorem.

Solution: In △ABC,

∠∠A = 60,∠C=80,

∴∠ABC= 180 -∠A-∠C-=40,

∫BD is the bisector of ∞∠ABC,

∴∠EBD= 1/2∠ABC=20,

∫DE∨BC,

∴∠EDB=∠DBC=20,

Then ∠ bed =180-∠ EBD-∠ EDB =180-20 =140.

Therefore, the internal angles of △BDE are: ∠ EBD = 20, ∠ EDB = 20, ∠ Bed = 140.

The fastest answer, hope to adopt, thank you.