Question

qual o valor numerico da expressão 3a - b/1 - a para a = - 1 e b = 3 ?

Answer 1

$\dfrac{3a-b}{1-a} \\\\Para:~~~~ a=-1~~~e~~~b=3\\\\\\ \dfrac{3(-1)-3}{1-(-1)}\to~~~ \dfrac{-3-3}{1+1}\to~~~\dfrac{-6}{2}\to~~~ \large\boxed{~~-3}$