Question

Determine x e y na proporção 4/9 = x + y / x sabendo que x + y = 20

Answer 1

4 x + y

--- = -------

9 x

4 20

--- = ----

9 x

4 . x = 20 . 9

4x = 180

x = 180

-----

4

x = 45

x + y = 20

45 + y = 20

y = 20 - 45

y = - 25