在三角形ABC中,角c=90度DE垂直平分AB,角CAD:角BAD=2:3,则角ADB的度数是?

来源:百度知道 编辑:UC知道 时间:2024/05/12 16:55:57
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60

解:∵△ABC中,∠ACB=90°,DE是AB的垂直平分线,
∴AD=BD,即∠BAD=∠ABD,
∵∠CAD:∠BAD=4:1,
设∠BAD=x,则∠CAD= 2/3x,
∵∠BAD+∠CAD+∠ABD=90°,即x+ 2/3x+x=90°,
解得:x=33.75°,
∠ADB=180°-2*33.75=112.5°

D点和E点分别落在那条线上?