1、
3a-5b+19=0 (1)
a+8b-1=0 (2)
(1)+(2)
4a+3b+18=0
4a+3b=-18
2、
3a-5b+19=0 (1)
a+8b-1=0 (2)
(1)-(2)
2a-13b+20=0
2a-13b=-20
4a-26b=-40
3、
3a-5b+19=0 (1)
a+8b-1=0 (2)
(2)×3-(1)
3a+24b-3-3a+5b-19=0
29b-22=0
b=22/29
a=1-8a=-147/29
1、
3a-5b+19=0 (1)
a+8b-1=0 (2)
(1)+(2)
4a+3b+18=0
4a+3b=-18
2、
3a-5b+19=0 (1)
a+8b-1=0 (2)
(1)-(2)
2a-13b+20=0
2a-13b=-20
4a-26b=-40
3、
3a-5b+19=0 (1)
a+8b-1=0 (2)
(2)×3-(1)
3a+24b-3-3a+5b-19=0
29b-22=0
b=22/29
a=1-8a=-147/29