Question

Poderiam responder essa questão 9?

Answer 1

$\frac{5}{1} = \frac{x}{3-x}$
15-5x=x
15=x+5x
15=6x
x=$\frac{15}{6}$
x=2,5

A= $\frac{5 .3}{2} - \frac{5 . 2,5}{2}$
A=$\frac{15}{2} - \frac{12,5}{2}$=
A= $\frac{2,5}{2}$=
A=$\frac{5}{4}$
resposta item B