7+(x-3y)/4=2x-(y+5)/3
[10(x-y)-4(1-x)]/3=y
去分母
7*12+3(x-3y)=12*2x-4(y+5)
10(x-y)-4(1-x)=3y
整理得:
21x+5y=104
14x-13y=4
①*2 ②*3得
42x+10y=208
42x-39y=12
解得 y=4
x=4
③④⑤
7+(x-3y)/4=2x-(y+5)/3 `````````①
[10(x-y)-4(1-x)]/3=y ``````` ②
①式*12得104-5y=21x `````````③
②式*3得14x-13y=4 `````````④
由③得x=(104-5y)/21 `````````⑤
将⑤带入④得y=4
将y=4带入⑤得x=4
所以x=4,y=4
x=4;y=4