Question

Daca (3x+y)/(x+2y), aflați x/y.

Answer 1

Răspuns:

Explicație pas cu pas:

(3x+y)/(x+2y) = 4/5

in proportie produsul mezilor = produsul extremilor

5(3x + y) = 4(x + 2y)

15x + 5y = 4x + 8y

15x - 4x = 8y - 5y

11x = 3y

x/y = 3/11

Answer 2

$\dfrac{3x+y}{x+2y} =\dfrac{4}{5} \Rightarrow (3x+y)\cdot5=4\cdot(x+2y)\Rightarrow 15x+5y=4x+8y\Rightarrow \\\\\Rightarrow 15x-4x=8y-5y\Rightarrow 11x=3y\Rightarrow \boxed{\dfrac{x}{y}=\dfrac{3}{11} }$