Răspuns:246:(5xa-9+1-0)-(130-20)=13
246:(5xa-10-0)-110=13
246:(5xa-10)=110-13
246:(5xa-10)=97
5xa-10=246:47
5xa-10=5
a-10=5x5
a-10=25
a=25-10
a=15
SPER CA TE-AM AJUTAT!