1) a-b= 95
a= 6b+5
6b+5-b=95
5b= 90
b=18, a = 95+18= 113
2) a+ b =615
b=a+1
a+ a+1 = 615
2a = 614
a=614:2= 307
4) a+b=89
a=3b+1
3b+1+b=89
4b=88
b=88:4=22
a=89-22=67
5) b=a-143
a=2b+56
b=2b+56-143
b=87
a= 143+ 87=230
la pct 3) e ceva gresit parerea mea
sper ca am fost de folos