8) a=Ana
m=Mihai
a+m=2017
a-7 =4m a=4m+7
a+m=2017 => 4m+7 +m =2017
5m =2010
m=402
a=2017 -m=1615 Ana=1615 lei Mihai =402 lei
9) m+a =2000
m-293=a-431 => m=a-431+293=a-138
a-138 +a =2000
2a =2138
a=1068
m=2000-1068=932
10)a+m =40
a-6=m+6 => a=m+12
a+m=40 => m+12+m=40
2m=28
m=14
a=40-14=26
11) a+b=630
a:b=2 rest 96 => a=2b+96
2b +96+b=630
3b=534
b=178
a=630-178 =452
