Questão 2794032

\(\left\{\begin{matrix} a+b=12 \\ a=12 \cdot b \end{matrix}\right.\)

\(\left\{\begin{matrix} a+b=12 \\ a=b \cdot b \end{matrix}\right.\)

\(\left\{\begin{matrix} a+b=12 \\ a-b = b \end{matrix}\right.\)

\(\left\{\begin{matrix} a+b=12 \\ a=b /2 \end{matrix}\right.\)

\(\left\{\begin{matrix} a+b=12 \\ a=2+b \end{matrix}\right.\)