阅读下列解方程组的方法,然后解答问题:解方程组
时,由于
的系数及常数项的数值较大,如果用常规的代入消元法、加减消元法来解,不仅计算量大,而且易出现运算错误.而采用下面的解法则比较简单:
①-②得
,所以
③
③
-①得
,
解得
,从而![](https://staticzujuan.xkw.com/quesimg/Upload/formula/107babba45f110012183dc4dc54490f7.png)
所以原方程组的解是
.
(1)请你运用上述方法解方程组:![](https://staticzujuan.xkw.com/quesimg/Upload/formula/182ccd6c51086b002c745d5651a53b1c.png)
(2)猜测关于
的方程组
的解是什么?请从方程组的解的角度加以验证.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fa70dbdfc4b226d439b0c4dd93057867.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9b0fffbec1fe851795dfdd448bf0d165.png)
①-②得
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/eadbd008b38bf9a3bee771bdaebe34d5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5558c083d34cbb0a58d3ce1dc6f5778e.png)
③
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7167a27f75f51fcc2745cd1c8a5eb27a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b1ab5d58faddc64d5bbbbeb7f8cf2e24.png)
解得
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ef00713e73b8357cc7900144f5505bc6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/107babba45f110012183dc4dc54490f7.png)
所以原方程组的解是
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f5dd71078c27c8bc9417deb4c8467ff6.png)
(1)请你运用上述方法解方程组:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/182ccd6c51086b002c745d5651a53b1c.png)
(2)猜测关于
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a2e647c14561826ba9e396acc5a3792c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03b8667ec501b97fa45730a3fa184d2f.png)
更新时间:2023-04-15 18:53:08
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【推荐1】某出租车公司有
两种不同型号的汽车,用两辆
型车和一辆
型车装满货物一次可运货10吨;用一辆
型车和两辆
型车装满货物一次可运货11吨.某物流公司现有31吨货物,计划同时租用
型车
辆和
型车
辆,一次运完,且恰好每辆车都装满货物.
根据以上信息,解答下列问题:
(1)一辆
型车和一辆
型车都装满货物一次可分别运货多少吨?
(2)请你帮该物流公司设计租车方案.
(3)若
型车每辆需租金200元/次,
型车每辆需租金240元/次.该物流公司最省钱的租车方案是 ,最少租车费为 元.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e52586ca2a3b783bc8092415e2d4bf6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c94bb12cee76221e13f9ef955b0aab1.png)
根据以上信息,解答下列问题:
(1)一辆
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
(2)请你帮该物流公司设计租车方案.
(3)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
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【推荐2】如果一个正整数的各数位上的数字都相同,则称这样的数为“叠合数”,比如:3,44,777,6666,…;对任意一个三位数n,如果n满足各数位上的数字互不相同,且都不为零,那么称这个数为“互异数”.将一个“互异数”任意两个数位上的数字对调后可以得到三个不同的新三位数,把这三个新三位数的和记为
.如
,对调百位与十位上的数字得到314,对调百位与个位上的数字得到431,对调十位与个位上的数字得到143.这三个新三位数的和
,是一个“叠合数”.
(1)计算:
,
,并判断它们是否为“叠合数”;
(2)若“互异数”
(其中p、q都是正整数,
,
),且
为最大的三位“叠合数”,求n的值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/081fad2749f3f201cf2c324c3d0dd190.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9bf7ac1c3baf41fba3ec0ab0282cf795.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/43eeb62fd55fdc8c9fcb1f4fb708d97e.png)
(1)计算:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ba3ff57aaf1d095dc1eb9a58df296770.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c94e829b179eec9ce0e7f6e7be3941a6.png)
(2)若“互异数”
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/65600032eeda98cee2a39c55cf01e7c5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/202da60321545b792c362bee9df5e80f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/376016bb83e37481b0166e9fc5c9c3bf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/081fad2749f3f201cf2c324c3d0dd190.png)
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【推荐1】解方程(不等式)组
(1)解方程组
;(2)解不等式组
(1)解方程组
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4489ece0441aabbbb68e0b5944a3e4ff.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4f9d61e68f688b7d48228425b082f551.png)
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