a)a-b =56.3 ;a =56.3-b inlocuim in urmatoarea relatie
a+b =84.2
56.3+b +b =84.2
56.3+2b =84.2
2b =84.2-56.3
2b =27.9
b =13.95
a+b =84.2
a +13.95 =84.2
a =84.2-13.95
a =70.25
b)a -b =125.4
b =a/10 ;a =10b inlocuim in prima relatie
10b -b =125.4
9b =125.4
b =13.93
a =10b
a =13.93*10
a =139.3