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题目 #18525

UUID
56460cb2-8233-4666-bbab-74e9ec6422d3
来源
A中考/2026江苏中考期末数学试卷+答案535.pdf 第 2 页,bbox [45.0, 498.03, 566.64, 511.77]
题型 / 学科
fill_blank / math / SENIOR
知识树
KT_SENIOR_MATH_STANDARD
难度
难度 2 / 5 简单 · 单一知识点
QA 状态
PUBLISHED 重试 0 次,得分 0.938
最终题 ID
8736

最终题干渲染(f_body 预览)

如图,在△ABC中,∠BAC = 114°,点D在BC上,连接AD,若BA = BD,DA = DC,则∠B的度数为____.

答案 / 解析

答案(f_answer)

36°

解析(f_ways)

设∠B = x。因BA = BD,△ABD为等腰三角形,故∠BAD = ∠BDA = (180° - x)/2。又DA = DC,△ADC为等腰三角形,故∠DAC = ∠C。在△ABC中,内角和为180°,即x + ∠C + 114° = 180°,得∠C = 66° - x。另一方面,∠BDA是△ADC的外角,故∠BDA = ∠DAC + ∠C = 2∠C(因∠DAC = ∠C)。因此(180° - x)/2 = 2(66° - x),解得x = 36°。

原图与资产(1)

预览类型页source bboxhashURL本地路径
embedded_image2 [45.0, 512.58, 186.65, 576.48] afbc9c662053f908…
打开
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审计记录

阶段审计器结果得分依据(简短)
STRUCTURE structure-rule PASS 0.900
FORMULA formula-auditor PASS 1.000
KNOWLEDGE knowledge-auditor WARN -
VISION vision-auditor PASS 0.950
SOLVER blind-solver PASS 1.000
CRITIC critic PASS 1.000
SYMBOLIC symbolic-auditor PASS 1.000
COHERENCE coherence-auditor PASS 0.900
QUALITY_GATE quality-gate PASS 0.938
SOLVER blind-solver PASS 1.000
CRITIC critic PASS 1.000
AUTO_REPAIR_ATTEMPT answer-repair PASS 1.000
AUTO_FILL_ANSWER answer-repair WARN 1.000
VISION vision-auditor PASS 0.950

知识点(0)

无

正式题库记录(t_question.f_id=8736)

f_qkey
59512b46285974729066bc0ad2ed2b91
f_style / 难度
3 / 2
入库题干
如图,在△ABC中,∠BAC = 114°,点D在BC上,连接AD,若BA = BD,DA = DC,则∠B的度数为____.
入库答案
36°
入库解析
设∠B = x。因BA = BD,△ABD为等腰三角形,故∠BAD = ∠BDA = (180° - x)/2。又DA = DC,△ADC为等腰三角形,故∠DAC = ∠C。在△ABC中,内角和为180°,即x + ∠C + 114° = 180°,得∠C = 66° - x。另一方面,∠BDA是△ADC的外角,故∠BDA = ∠DAC + ∠C = 2∠C(因∠DAC = ∠C)。因此(180° - x)/2 = 2(66° - x),解得x = 36°。

事件

时间阶段级别消息
2026-09-24 04:46:23PUBLISHINFO已发布 t_question.f_id=8736 qkey=59512b46285974729066bc0ad2ed2b91
2026-09-24 04:46:23QAINFOQA: PASS (score=0.938)