As shown in the figure, in the quadrilateral ABCD, ∠ a = 104 °- ∠ 2, ∠ ABC = 76 °+ ∠ 2, BD ⊥ CD in D, EF ⊥ CD in F, can you identify ∠ 1 = ∠ 2? Try to explain the reason
The reasons are as follows: ∵ a = 104 ° - 2, ∵ ABC = 76 ° + 2, ∵ a + ABC = 104 ° - 2 + 76 ° + 2 = 180 °, ∵ ad ∥ BC (complementary inner angle on the same side, two lines are parallel), ∵ 1 = DBC (two lines are parallel, equal inner stagger angle),
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