题目内容
如图:CD平分∠ACB,DE∥BC,∠ADE=45°,∠A=48°,则∠CDE=______.
![](http://thumb.zyjl.cn/pic2/upload/papers/20140825/201408252041238412004.png)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140825/201408252041238412004.png)
∵DE∥BC,
∴∠ABC=∠ADE,
∴△ABC中∠ACB=180°-∠ADE-∠A=180°-45°-48°=87°,
∵CD平分∠ACB,
∴∠DCB=
∠ACB=43.5°,
∵DE∥BC,
∴∠CDE=∠DCB=43.5°.
∴∠ABC=∠ADE,
∴△ABC中∠ACB=180°-∠ADE-∠A=180°-45°-48°=87°,
∵CD平分∠ACB,
∴∠DCB=
1 |
2 |
∵DE∥BC,
∴∠CDE=∠DCB=43.5°.
![](http://thumb.zyjl.cn/images/loading.gif)
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