3(X-1)+2(Y+1)=8 2(X-1)-3Y=1的解

题目

3(X-1)+2(Y+1)=8 2(X-1)-3Y=1的解

答案

3(X-1)+2(Y+1)=8
3X-3+2Y+2=8
3X+2Y=9 (1)
2(X-1)-3Y=1
2X-2-3Y=1
2X-3Y=3 (2)
(1)×3+(2)×2
9X+4X=27+6
13X=33
所以
X=33/13
Y=(9-3X)/2=9/13