4a-3b=27 2a+3b=68 a= b=6a-2b=49 2a+3b=86 a= b=2a+3b=100 3a+2b=120 a= b=

4a-3b=27 2a+3b=68 a= b=6a-2b=49 2a+3b=86 a= b=2a+3b=100 3a+2b=120 a= b=
4a-3b=27 2a+3b=68 a= b=
6a-2b=49 2a+3b=86 a= b=
2a+3b=100 3a+2b=120 a= b=

4a-3b=27 2a+3b=68 a= b=6a-2b=49 2a+3b=86 a= b=2a+3b=100 3a+2b=120 a= b=
4a-3b=27 2a+3b=68
相加,得
6a=95
a=95/6,b=109/9
6a-2b=49 2a+3b=86 \
11b=86×3-49
b=209÷11=19
a=（49+2×19）÷6=14.5
2a+3b=100
3a+2b=120
相加,得
5a+5b=220
a+b=44
a=120-44×2=32
b=44-32=12

6a-2b=49 a=(49+2b)/6
2a=(49+2b)/3
(49+2b)/3+3b=86 b=19
a=(49+2b)/6=(49+2*19)/6=14.5

2a+3b=100 3a+2b=120
5a+5b=220
a+b=44 a=44-b
2(44-b)+3b=100 b=12
a=44-b=44-12=32