As shown in the figure, rectangular ABCD, e is a point on AB, fold the triangle CEB along CE, let Ge intersect DC at point F, if ∠ EFD = 80 °, calculate the degree of ∠ BCE

∵ quadrilateral ABCD is a rectangle, ∥ ab ∥ CD, ∥ B = 90 ° and ∥ bef = ∥ DFE = 80 ° according to the nature of folding: ∥ BEC = ∥ FEC = 40 ° then ∥ BCE = 90 ° - ∥ BEC = 50 °

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