如图5所示,AB=AC,AD=AE,∠BAC=∠DAE,∠1=25°,∠2=30°,则∠3=_____http://www.google.cn/search?hl=zh-CN&newwindow=1&rlz=1T4XNLA_zh-CNCN295CN295&q=%E5%A6%82%E5%9B%BE5%E6%89%80%E7%A4%BA%2CAB%3DAC%2CAD%3DAE%2C%E2%88%A0BAC%3D%E2%88%A0DAE%2C%E2%88%A

来源:学生作业帮助网 编辑:六六作业网 时间:2024/12/18 23:40:03
如图5所示,AB=AC,AD=AE,∠BAC=∠DAE,∠1=25°,∠2=30°,则∠3=_____http://www.google.cn/search?hl=zh-CN&newwindow=1&

如图5所示,AB=AC,AD=AE,∠BAC=∠DAE,∠1=25°,∠2=30°,则∠3=_____http://www.google.cn/search?hl=zh-CN&newwindow=1&rlz=1T4XNLA_zh-CNCN295CN295&q=%E5%A6%82%E5%9B%BE5%E6%89%80%E7%A4%BA%2CAB%3DAC%2CAD%3DAE%2C%E2%88%A0BAC%3D%E2%88%A0DAE%2C%E2%88%A
如图5所示,AB=AC,AD=AE,∠BAC=∠DAE,∠1=25°,∠2=30°,则∠3=_____
http://www.google.cn/search?hl=zh-CN&newwindow=1&rlz=1T4XNLA_zh-CNCN295CN295&q=%E5%A6%82%E5%9B%BE5%E6%89%80%E7%A4%BA%2CAB%3DAC%2CAD%3DAE%2C%E2%88%A0BAC%3D%E2%88%A0DAE%2C%E2%88%A01%3D25%C2%B0%2C%E2%88%A02%3D30%C2%B0%2C%E5%88%99%E2%88%A03%3D_____&btnG=Google+%E6%90%9C%E7%B4%A2&meta=&aq=f&oq=
有图!

如图5所示,AB=AC,AD=AE,∠BAC=∠DAE,∠1=25°,∠2=30°,则∠3=_____http://www.google.cn/search?hl=zh-CN&newwindow=1&rlz=1T4XNLA_zh-CNCN295CN295&q=%E5%A6%82%E5%9B%BE5%E6%89%80%E7%A4%BA%2CAB%3DAC%2CAD%3DAE%2C%E2%88%A0BAC%3D%E2%88%A0DAE%2C%E2%88%A
根据题意可证明
∠EAC=∠DAB
而AB=AC,AD=AE
所以根据SAS得到:
三角形ABD全等于三角形ACE
所以∠ABD=∠2=30°,
所以∠3°=∠1+∠ABD
=25°+30°
=55°

图形?没有看到