如圖所示,兩塊三角板的直角頂點
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重疊在一起,且
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恰好平分
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,則
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的度數(shù)是
。
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試題分析:由
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恰好平分
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可得∠BOD的度數(shù),再加上∠AOB即可得到結果.
∵
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平分
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,
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=90°
∴∠BOD=45°
∵∠AOB=90°
∴
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=∠AOB+∠BOD=135°.
點評:本題屬于基礎應用題,只需學生熟練掌握角平分線的性質,即可完成.
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