Question

a diferença entre o quádruplo de x e 1 é maior que 20

Answer 1

$4x-1\ \textgreater \ 20\\\\4x\ \textgreater \ 20+1\\\\4x\ \textgreater \ 21\\\\\boxed{x\ \textgreater \ \dfrac{21}{4}}\\\\\\\boxed{\boxed{S=\left\{x\in\mathbb{R}\ \left|\ x\ \textgreater \ \dfrac{21}{4}\right\right\}}}$