第1个回答 2015-12-04
解:由前式得:y=3x-5
代到后式中:5(3x-5)-1=3x+5
解此方程得:15x-25-1=3x+5
12x=31,即x=31/12
因此y=(3*31/12)-5=(31/4)-5=11/4
所求x=31/12;y=11/4
第2个回答 推荐于2016-12-01
3x-y=5 (1)
5y-1=3x+5 (2)
y=3x-5 (3)
5y-3x=6 (4)
把(3)带入(4)式得:
5(3x-5)-3x=6
解得:x=31/12
y=11/4本回答被提问者和网友采纳
第3个回答 2015-04-24
3x-y=5 (1)
5y-1=3x+5
3x-5y=-6 (2)
(1)-(2)
4y=11
y=11/4
from (1)
3x-11/4 =5
x= 3/4
第4个回答 2015-04-24
![](https://video.ask-data.xyz/img.php?b=https://iknow-pic.cdn.bcebos.com/8c1001e93901213f3cc58ff851e736d12f2e9524?x-bce-process=image%2Fresize%2Cm_lfit%2Cw_600%2Ch_800%2Climit_1%2Fquality%2Cq_85%2Fformat%2Cf_auto)
追答x=31/12 y=21/4
楼下和我刚刚的回答都错了,
![](https://video.ask-data.xyz/img.php?b=https://iknow-pic.cdn.bcebos.com/a8014c086e061d952a34f91c7ef40ad162d9caa0?x-bce-process=image%2Fresize%2Cm_lfit%2Cw_600%2Ch_800%2Climit_1%2Fquality%2Cq_85%2Fformat%2Cf_auto)
这才是正解
x=31/12 y=11/4