2/3u + 3v/4 =1/2 4/5u + 5v/6 =7/15

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2/3u + 3v/4 =1/2 4/5u + 5v/6 =7/15
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2/3u + 3v/4 =1/2 4/5u + 5v/6 =7/15
2/3u + 3v/4 =1/2 4/5u + 5v/6 =7/15

2/3u + 3v/4 =1/2 4/5u + 5v/6 =7/15
答:
2/3u + 3v/4 =1/2…………(1)
4/5u + 5v/6 =7/15…………(2)
(1)两边同时乘以12、(2)两边同时乘以30得:
8u+9v=6………………(3)
24u+25v=14…………(4)
(1)*3-(2)得:
27v-25v=18-14
2v=4
解得:v=2
代入(3)得:8u+18=6
解得:u=-1.5
所以:方程组的解为u=-1.5,v=2