解方程组3(X+Y)-5(X-Y)16 2(X+Y)-1(X-Y)=15

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解方程组3(X+Y)-5(X-Y)162(X+Y)-1(X-Y)=15解方程组3(X+Y)-5(X-Y)162(X+Y)-1(X-Y)=15解方程组3(X+Y)-5(X-Y)162(X+Y)-1(X-

解方程组3(X+Y)-5(X-Y)16 2(X+Y)-1(X-Y)=15
解方程组3(X+Y)-5(X-Y)16 2(X+Y)-1(X-Y)=15

解方程组3(X+Y)-5(X-Y)16 2(X+Y)-1(X-Y)=15
3(X+Y)-5(X-Y)=16
2(X+Y)-1(X-Y)=15
设X+Y=a X-Y=b
则有
3a-5b=16 (1)
2a-b=15 (2)
(1)*2-(2)*3得b=13/7
则a=59/7
则X=36/7 Y=23/7

你打清楚些,哪里方程组,就一个方程嘛
难道16前是等于撒

-2x+8y=16 y=23/7
x+3y=15 x=36/7