Question

如图一个弯形管道ABCD的拐角<ABC=120·,<BCD=60·，这时说管道AB//CD对吗?为什么?

Answer 1

解：∵∠ABC=120°，∠BCD=60°，
∴∠ABC+∠BCD=120°+60°=180°，
∴AB∥CD（同旁内角互补，两直线平行）．

Answer 2

解：∵∠ABC=120°，∠BCD=60°，
∴∠ABC+∠BCD=120°+60°=180°，
∴AB∥CD（同旁内角互补，两直线平行）．

Answer 3

AB//CD因为同旁内角互补，两直线平行

Answer 4

AB//CD因为同旁内角互补，两直线平行

Answer 5

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