Question

afla nr natural caruia acasa ii adaugam dublul lui 15 si obtinem 73

Answer 1

a+2×15=73
a+30=73
a=73-30
a=43

Answer 2

${ \mathbf{ x \: + \: 2 \cdot 15 = 73}} = = > \\ x \: + \: 30 = 73 = = > \\ x = 73 - 30 = = > \\ \it x = 43$