Salut! =)
[tex]\frac{3x+y}{x+2y} = \frac{4}{5}[/tex]
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[tex]\frac{x}{y} =?[/tex]
5 ( 3x + y ) = 4 ( x + 2y )
15x + 5y = 4x + 8y
15x - 4x = 8y - 5y
11x = 3y => x = [tex]\frac{3y}{11}[/tex]
[tex]\frac{\frac{3y}{11} }{y} = \frac{3y}{11 } * \frac{1}{y} = \frac{3y}{11y} = \frac{3}{11}[/tex]
Bafta! =)
