解方程组24/(x+y) +24/(x-y) = 7/3 ,8/(x+y) +18/(x-y) = 4/3

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解方程组24/(x+y) +24/(x-y) = 7/3 ,8/(x+y) +18/(x-y) = 4/3
解方程组24/(x+y) +24/(x-y) = 7/3 ,8/(x+y) +18/(x-y) = 4/3

解方程组24/(x+y) +24/(x-y) = 7/3 ,8/(x+y) +18/(x-y) = 4/3
因为8/(x+y) +18/(x-y) = 4/3,两边乘以3得
24/(x+y) +54/(x-y) = 4
两边同时减去
24/(x+y) +24/(x-y) = 7/3

30/(x-y) = 5/3
所以x-y=18
代入
8/(x+y) +18/(x-y) = 4/3
得x+y = 24
所以x=21, y=3
谢谢采纳 ^_^

设1/(x+y)=A,1/(x-y)=B,则原方程组化为:
24A+24B=7/3,
8A+18B=4/3,
解得:A=1/24,B=1/18。
即1/(x+y)=1/24,1/(x-y)=1/18,
x+y=24,
x-y=18,
解得:x=21,y=3。
代入原方程组,检验:方程组成立。
所以原方程组的解为:x=21,y=3。