Question

5(13-3b/5)+3b=13

preciso de ajuda nessa distributiva

Answer 1

$5\left (\dfrac{13-3b}{5}\right)+3b=13\\\\\\\dfrac{65}{5}-\dfrac{15b}{5}+3b=13\\\\\\13-3b\hspace{-7}\diagup+3b\hspace{-7}\diagup=13\\\\\\13=13\\\\\\\text{Como a vari\'avel sempre se anula, b pode ser qualquer n\'umero}\\\text{do conjunto dos reais:}~~b\in \mathbb{R}\\\\ \fbox{\fbox{ ]-\infty,+~\infty~[~=~{\mathbb{R}} }}$