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
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 14:24:18 | PUBLISH | INFO | 已发布 t_question.f_id=10693 qkey=6d1f14963e03874ca31a0314516009c6 |
| 2026-09-25 14:24:18 | QA | INFO | QA: PASS (score=0.950) |
| 2026-09-25 14:17:51 | FORMULA | WARN | 公式转换疑似填入原题空白,保留源文本: stem |