已知:如图,AD⊥BC于点D,EG⊥BC于点G,∠E=∠3,那么AD是∠BAC的平分线吗?若是,请说明理由.请完成下列证明并在下面的括号内填注依据.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/7/28/4748cd46-ed53-486e-98d0-337434d5609f.png?resizew=188)
解:是,理由如下:
∵AD⊥BC,EG⊥BC(已知),
∴∠4=______=90°(垂直定义),
∴______(同位角相等,两直线平行),
∴∠1=∠E(____________);
∠2=______(两直线平行,内错角相等).
∵∠E=∠3(已知),
∴∠1=∠2(等量代换),
∴AD平分∠BAC(____________).
![](https://img.xkw.com/dksih/QBM/editorImg/2022/7/28/4748cd46-ed53-486e-98d0-337434d5609f.png?resizew=188)
解:是,理由如下:
∵AD⊥BC,EG⊥BC(已知),
∴∠4=______=90°(垂直定义),
∴______(同位角相等,两直线平行),
∴∠1=∠E(____________);
∠2=______(两直线平行,内错角相等).
∵∠E=∠3(已知),
∴∠1=∠2(等量代换),
∴AD平分∠BAC(____________).
更新时间:2022-07-25 19:15:23
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【推荐2】推理填空:如图,已知
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又∵
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∴
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