题目

四边形ACBD为的内接四边形，已知：：5，则______度 答案：【答案】80【解析】根据圆的内接四边形对角互补解答即可．因为四边形ABCD为⊙O的内接四边形，∠A：∠C＝4：5，可设∠A为4x，∠C为5x，可得：4x+5x＝180°，解得：x＝20°，所以∠A＝80°，故答案为：80.-I have driven for so long, and now I want to have a rest. - _______ . _______ to drive. A. No; It's my turn B. Yes; It's your turnC. Go ahead; It's your turn D. Go ahead; It's my turn