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题目 #23163

UUID
a3c0f2e2-809d-46c8-be72-936f7645a216
来源
人教版/七下/2026江苏七年级期末数学试卷+答案955.pdf 第 1 页,bbox [30.22, 359.49, 347.62, 457.55]
题型 / 学科
single_choice / 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 0.950
最终题 ID
10693

最终题干渲染(f_body 预览)

用加减法解方程组{2x −3y = 3①3x −2y = 5②,下列解法错误的是(      )
A. ①\(\times 3\)−②\(\times 2\),消去x
B. ①\(\times (−3) +\)②\(\times 2\),消去x
C. ①\(\times 2 +\)②\(\times (−3)\),消去y
D. ①\(\times 2\)−②\(\times (−3)\),消去y

答案 / 解析

答案(f_answer)

D

解析(f_ways)

方程组为:①\(2x-3y=3\),②\(3x-2y=5\)。 A. ①\(\times 3−②\times 2\):\((2x-3y)\times 3 - (3x-2y)\times 2 = 6x-9y - (6x-4y) = -5y = 9-10 = -1\),消去了\(x\),正确。 B. ①\(\times (−3)+②\times 2\):\((2x-3y)\times (-3) + (3x-2y)\times 2 = -6x+9y + 6x-4y = 5y = -9+10 = 1\),消去了\(x\),正确。 C. ①\(\times 2+②\times (−3)\):\((2x-3y)\times 2 + (3x-2y)\times (-3) = 4x-6y -9x+6y = -5x = 6-15 = -9\),消去了\(y\),正确。 D. ①\(\times 2−②\times (−3)\):\((2x-3y)\times 2 - (3x-2y)\times (-3) = 4x-6y - (-9x+6y) = 4x-6y+9x-6y = 13x-12y = 6+15 = 21\),无法消去\(y\),错误。 故选:D

原图与资产(0)

该题没有裁出图片资产

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 1.000
SOLVER blind-solver PASS 1.000
CRITIC critic PASS 1.000
SYMBOLIC symbolic-auditor PASS 1.000
COHERENCE coherence-auditor FAIL 0.900
QUALITY_GATE quality-gate FAIL 0.950
SOLVER blind-solver PASS 0.950
CRITIC critic PASS 0.950
COHERENCE coherence-auditor PASS 1.000
SYMBOLIC symbolic-auditor PASS 1.000
AUTO_REPAIR_ATTEMPT answer-repair PASS 1.000
AUTO_REPAIR answer-repair PASS 1.000
VISION vision-auditor PASS 1.000

知识点(0)

无

正式题库记录(t_question.f_id=10693)

f_qkey
6d1f14963e03874ca31a0314516009c6
f_style / 难度
1 / 2
入库题干
用加减法解方程组{2x −3y = 3①3x −2y = 5②,下列解法错误的是(      )
A. ①\(\times 3\)−②\(\times 2\),消去x
B. ①\(\times (−3) +\)②\(\times 2\),消去x
C. ①\(\times 2 +\)②\(\times (−3)\),消去y
D. ①\(\times 2\)−②\(\times (−3)\),消去y
入库答案
D
入库解析
方程组为:①\(2x-3y=3\),②\(3x-2y=5\)。 A. ①\(\times 3−②\times 2\):\((2x-3y)\times 3 - (3x-2y)\times 2 = 6x-9y - (6x-4y) = -5y = 9-10 = -1\),消去了\(x\),正确。 B. ①\(\times (−3)+②\times 2\):\((2x-3y)\times (-3) + (3x-2y)\times 2 = -6x+9y + 6x-4y = 5y = -9+10 = 1\),消去了\(x\),正确。 C. ①\(\times 2+②\times (−3)\):\((2x-3y)\times 2 + (3x-2y)\times (-3) = 4x-6y -9x+6y = -5x = 6-15 = -9\),消去了\(y\),正确。 D. ①\(\times 2−②\times (−3)\):\((2x-3y)\times 2 - (3x-2y)\times (-3) = 4x-6y - (-9x+6y) = 4x-6y+9x-6y = 13x-12y = 6+15 = 21\),无法消去\(y\),错误。 故选:D

事件

时间阶段级别消息
2026-09-25 14:24:18PUBLISHINFO已发布 t_question.f_id=10693 qkey=6d1f14963e03874ca31a0314516009c6
2026-09-25 14:24:18QAINFOQA: PASS (score=0.950)
2026-09-25 14:17:51FORMULAWARN公式转换疑似填入原题空白,保留源文本: stem