Question

o dobro desse numero é igual a quinta parte deste numero menos 36

Answer 1

$2x= \frac{x}{5} -36\to ~~mmc=5\\\\ 10x=x-180\to \\\\ 10x-x=-180\to \\\\ 9x=-180\to \\\\ x=- \dfrac{180}{9} \to \\\\ \boxed{x=-20}$