Question

O valor de x na proporção a) 3 b)​

Answer 1

Resposta: b) 1/3

$\frac{3-x}{1+x} = \frac{4}{2} \\\\ 2(3-x) = 4(1+x)\\6 - 2x = 4 + 4x\\6 - 4 = 4x + 2x\\2 = 6x\\x = 2/6\\x = 1/3$