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1、华东师大版2019-2020 学年七年级下册数学第六章一元一次方程单元卷含答案一、选择题（每小题3 分，共 30 分）1.下列方程为一元一次方程的是()A.y=3 B.x+2y=3 C.x2=2x D.1y+y=22.下列变形正确的是（）A.由 ac=bc，得 a=b B.由?5=?5-1，得 a=b1 C.由 2a3=a，得 a=3 D.由 2a1=3a+1，得 a=2 3.小宝今年 5 岁，妈妈35 岁，（）年后，妈妈的年龄是小宝的2 倍.A.30 B.20 C.10 D.25 4.下列方程中，解为x=-2 的方程是()A.x-2=0 B.2+3x=-4 C.3x-1=2 D.4-2x=3
2、 5.在解方程2?-12=1-3-?3时，去分母后正确的是（）A.3(2?-1)=1-2(3-?)B.3(2?-1)=1-(3-?)C.3(2?-1)=6-2(3-?)D.2(2?-1)=6-3(3-?)6.某商店同时卖出两件衣服，每件135 元，若按成本计，其中一件盈利25%，另一件亏损25%,那么这两件衣服卖出后，商店（）A.不亏不赔 B.赚 9 元 C.赔 18 元 D.赚 18 元7.对于任意两个有理数a、b，规定 a?b=3ab，若（2x+3）?（3x1）=4，则 x 的值为（）A.1 B.1 C.2 D.2 8.A 种饮料比 B 种饮料单价少1 元，小峰买了2 瓶 A 种饮料和3
3、瓶 B 种饮料，一共花了13 元，如果设A种饮料单价为x 元/瓶，那么下面所列方程正确的是A.2(x1)3x 13 B.2(x 1)3x 13 C.2x 3(x 1)13 D.2x 3(x1)13 9.根据如图所示的计算程序，若输出的值y=-1，则输入的值x为（）A.2 B.-4 或 1 或-1 C.-4 或 1 D.-4 或-1 10.已知一个由50 个偶数排成的数阵用如图所示的框去框住四个数，并求出这四个数的和在下列给出备选答案中，有可能是这四个数的和的是（）精品w o r d 可编辑资料-第 1 页，共 7 页-A.80 B.148 C.172 D.220 二、填空题（每小题3 分，共
4、18 分）11.已知 x=4 是关于 x 的方程 3x2a=9 的解，则a的值为 _.12.当 x=_时，4x4 与 3x10 互为相反数.13.一个两位数，十位数字是个位数字的2 倍，将两个数对调后得到的两位数比原来的两位数小36，这个两位数是 _14.一张试卷只有25 道选择题，做对一题得4 分，做错 1 题倒扣 1分，某同学做了全部试题共得85 分，他做对了 _道题15.如图，方格中的格子填上数，使得每一行、每一列以及两条对角线所填的数字之和均相等，则x 的值为_16.某客运站行车时刻表如图，若全程保持匀速行驶，则当快车出发_小时后，两车相距25km.哈尔滨 长春 出发时间 到站时间 里
5、程（km）普通车7:00 11:00 300 快车7:30 10:30 300 三、解答题（共6 题；共 52 分）17.解下列方程（1）3x+2=8-x（2）3?-13=1-4?-1618.某个商品的进价是500 元，把它提价40%后作为标价.如果商家要想保住12%的利润率搞促销活动，请你计算一下广告上可写出打几折？19.在甲处植树的学生有31 人，在乙处植树的学生有21 人，现派23 名学生到甲、乙两处支援，使得甲处植树的人数是乙处植树人数的2 倍.应往甲、乙两处各派多少名学生？20.甲乙两车从相距240 km 的两站同时开出，相对而行，甲车每小时行50km，乙车每小时行30km，问出发几
6、小时后两车相距80km?21.为庆祝建国七十周年，南岗区准备对某道路工程进行改造，若请甲工程队单独做此工程需4个月完成，若请乙工程队单独做此工程需6 个月完成，若甲、乙两队合作2 个月后，甲工程队到期撤离，则乙工程队再单独需几个月能完成？精品w o r d 可编辑资料-第 2 页，共 7 页-文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4
7、ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档
8、编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H
9、10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L
10、4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3
11、文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R
12、4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B
13、7L4 ZY3T4V8M3G322.某天，一蔬菜经营户用60元钱从蔬菜批发市场批发了萝卜和白菜共40kg到菜市场去卖，萝卜和白菜这天每千克的批发价与零售价如下表所示：品名萝卜 白菜批发价/元 1.6 1.2 零售价/元 2.5 1.8 问：他当天卖完这些萝卜和白菜共能赚多少钱？精品w o r d 可编辑资料-第 3 页，共 7 页-文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4
14、R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5
15、A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V
16、8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4
17、G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5
18、J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T
19、4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:C
20、T4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3华东师大版 2019-2020学年七年级下册数学第六章一元一次方程单元卷含答案一、选择题1.A、y=3 符合一元一次方程的定义；B、x+2y=3 含有 2 个未知数，不是一元一次方程；C、x2=2x中未知数的最高次数是2，不是一元一次方程；D、1y+y=2等号左边不是整式，不是一元一次方程，故答案为：A2.A.由 ac=bc，当 c=0 时，a 不一定等于b，错误；B.由?5=?5-1，得 a=b5，错误；C.由 2a3=a，得 a=3，正确；D.由 2a1=3a+1，得 a=2，错误.故答案为：C.3.设 x 年后，妈妈的
21、年龄是小宝的2 倍.根据题意，得2（5+x）=35+x 解得x=25 答：25 年后，妈妈的年龄是小宝的2 倍.故答案为：D.4.解：A、x-2=0，则 x=2，故 A 不符合题意；B、2+3x=-4 3x=-4-2 3x=-6 x=-2，故B符合题意；C、3x-1=2 3x=3 x=1，故 C不符合题意；D、4-2x=3-2x=-1?=12，故 D 不符合题意；故答案为：B.5.解：在解方程2?-12=1-3-?3=1 时，去分母得：3（2x-1）=6-2（3-x），故答案为：C.6.解：设盈利的衣服的进价为x元，亏损的衣服的进价为y 元，依题意，得：135-x 25%x，135-y-25%
22、y，解得：x108，y180，精品w o r d 可编辑资料-第 4 页，共 7 页-文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R
23、4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A
24、9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8
25、M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G
26、4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J
27、5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4
28、V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3135-108（135-180）-18，商店赔 18 元.故答案为：C.7.根据题意得：3（2x+3）-（3x1）=4，去括号得：6x+9-3x+1=4，移项合并得：3x=-6，
29、解得：x=-2.故答案为：D.8.设 A 种饮料单价为x 元/瓶，则 B种饮料单价为（x+1）元，根据小峰买了2 瓶 A 种饮料和3 瓶 B 种饮料，一共花了13 元，可得方程为：2x+3（x+1）=13故选 C9.解：当 x 为正数时，|x|-2=-1，解得 x=1；当 x 为负数时，x+3=-1，解得 x=-4.所以 x 的值为-4 或 1.故选 C.10.设框住的左上角的数为a，根据题意得：框住四个数分别为：a，a+2，a+12，a+14，则这四个数的和为a+（a+2）+（a+12）+（a+14）=4a+28，当 4a+28=80 时，解得：a=13；当 4a+28=148 时，解得：a
30、=30；当 4a+28=172 时，解得：a=36；当 4a+28=220 时，解得：a=48；此数阵是由50 个偶数排成的10 行 5 列的数阵，a（框住的左上角的数）只能为36，4a+28=4 36+28=172.故答案为：C.二、填空题11.解：把 x4 代入 3x2a=9 得：12-2a 9，解得：a32，故答案为：32.12.解：根据题意得：4x-4+3x-10=0，移项合并得：7x=14，解得：x=2，故答案为：2.13.解：设个位数字为x，则十位数字为2x，由题意得：10 2x+x-（10 x+2x）=36，精品w o r d 可编辑资料-第 5 页，共 7 页-文档编码:CT4
31、G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5
32、J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T
33、4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:C
34、T4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 H
35、I5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY
36、3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码
37、:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3解得：x=4，则 2x=8，答：原两位数是84故答案为 8414.设他做对了x 道题，则做错了（25x）道题，依题意得：4x（25x）85，解得 x22故答案是：2215.6+1+2153，6+1+2630，6+1+2054根据题意得：6+1+26+x+4，解得：x 1故答案为：
38、116.解：根据题意普通车的速度为：300 4=75km/h 快车的速度为：3003=100km/h.设快车出发x 小时后，两车相距25km，此时慢车出发x+0.5 小时 若快车追上慢车之前，则根据题意75(?+0.5)-100?=25解得?=0.5.此时时间为8:00 正确；若快车追上慢车之后，则根据题意100?-75(?+0.5)=25解得?=2.5.此时时间为10:30 正确.故出发 0.5 小时或 2.5 小时之后，两车相距25km.三、解答题17.（1）解：移项得 3x+x=8-2 合并同类项得 4x=6，系数化为 1 得 x=32；（2）解：方程两边都乘以6 约去分母得 2（3x-
39、1）=6-(4x-1),去括号得 6x-2=6-4x+1,移项得 6x+4x=6+1+2,合并同类项得 10 x=9，系数化为 1 得 x=910.精品w o r d 可编辑资料-第 6 页，共 7 页-文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T
40、4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:C
41、T4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 H
42、I5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY
43、3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码
44、:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10
45、 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G318.解：设该商品打x 折，依题意，则：500(1+40%)
46、0.1x=500（1+12%）.x=8.答：该商品的广告上可写上打八折.19.解：设应往甲处派x 名学生，则往乙处派（23-x）名学生.根据题意得：31+?=2 21+(23-?)?=19当 x=19 时，23-?=4.答：应往甲处派19 名学生，则往乙处派4 名学生.20.解：设出发x 小时后两车相距80km，根据题意，得50 x+30 x+80=240，或 50 x+30 x-80=240 解得 x=2，或 x=4 答：出发 2 小时或 4 小时后两车相距80km 21.解：设乙工程队再单独做此工程需x 个月能完成，甲工程队单独做此工程需4个月完成，若请乙工程队单独做此工程需6个月完成，甲
47、每个月完成14,乙工程队每个月完成16，现在甲、乙两队先合作2 个月，则完成了2(14+16)，由乙 x 个月可以完成16?，根据等量关系甲完成的+乙完成的=整个工程，列出方程为：2(14+16)+16?=1解得 x=1.22.解：设批发萝卜x kg，则批发白菜（40-x）kg.可列方程：1.6x+1.2（40-x）=60 解得：x=30 40-x=10(2.5-1.6)30+(1.8-1.2)10=33（元）答：他当天卖完这些萝卜和白菜共能赚33 元。精品w o r d 可编辑资料-第 7 页，共 7 页-文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档
48、编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H
49、10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L
50、4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3文档编码:CT4G4R4R4H10 HI5J5A9B7L4 ZY3T4V8M3G3