Question

daca a si b sunt doua numere naturale pentru care avem a+b =18 si a+3b=52 atunci a=......... si b=..........

Answer 1

a+b=18
a+3b=52
a=?
b=?
a=18-b
(18-b) + 3b =52
18-b+3b=52
18+2b=52
2b=52-18=34
b=34:2=17
b=17

a+b=18
a+17=18
a=1

Answer 2

a+b=18
a+3b=58=>a=3b+58
3b+58+b=18
4b+58=18
4b=58-18
4b=40=>b=40:4=>b=10
a+10=18
a=18-10
a=8