解方程组 {(x+y)/2+(x-y)/3=6 5(x+y)-2(x-y)=4

来源:学生作业帮助网 编辑:作业帮 时间:2024/04/28 03:12:06
解方程组 {(x+y)/2+(x-y)/3=6 5(x+y)-2(x-y)=4
xN0_%c1縡RhGxbHH@%2҆ &$6. JHBgLeӰ.P3 5]N )ā"*NO΢5Q{/1/3/4i 4`@{n.5 ? ! P[ybȸ *=HBj_ >VA"%Ƚ>I"y~|tY]X>W>es3˻ZtQe@$7I

解方程组 {(x+y)/2+(x-y)/3=6 5(x+y)-2(x-y)=4
解方程组 {(x+y)/2+(x-y)/3=6 5(x+y)-2(x-y)=4

解方程组 {(x+y)/2+(x-y)/3=6 5(x+y)-2(x-y)=4
(x+y)/2+(x-y)/3=6 ①
5(x+y)-2(x-y)=4 ②
由①得 3x+3y+2x-2y=36 5x+y=36 y=36-5x ③
由②得 5x+5y-2x+2y=4 3x+7y=4 ④
③代入④得 3x+252-35x=4
32x=248
x=7.75
代入③得y=36-5×7.75=-2.75

(X+Y)/2+(X-Y)/3=6方程两边同乘以6得3(X+Y)+2(X-Y)=36化简得5x+y=36
4(x+y)-5(x-y)=2化简得9y-x=2解方程组5x+y=36,9y-x=2得x=7y=1