Răspuns :
[tex] \frac{x + 2}{x + 4} = \frac{4}{5} \\ 5(x + 2) = 4(x + 4) \\ 5x + 10 = 4x + 16 \\ 5x - 4x = 16 - 10 \\ x = 6[/tex]
(x+2)/(x+4) = 4/5 ⇔ 5*(x+2) = 4*(x+4)
5x+10 = 4x+16
5x - 4x = 16 - 10
x = 6
5x+10 = 4x+16
5x - 4x = 16 - 10
x = 6