Question

Ex 12
Va rog ajutor!!

Answer 1

Răspuns:

Explicație pas cu pas:

x/y = 5/13 → proporție

x/5 = y/13 = k → coeficient de proporționalitate

x = 5k și y = 13k

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a)  ( x+y)/y = (5k+13k)/13k = 18k/13k = 18/13

b)  x/(y+x) = 5k/(13k+5k) = 5k/18k = 5/18

c) (y-x)/x = (13k-5k)/5k = 8k/5k = 8/5

Answer 2

$\it a)\ \dfrac{x}{y}=\dfrac{5}{13} \Rightarrow \dfrac{x+y}{y}=\dfrac{5+13}{13} \Rightarrow \dfrac{x+y}{y}=\dfrac{18}{13}\\ \\ \\ b)\ \dfrac{x}{y}=\dfrac{5}{13} \Rightarrow \dfrac{x}{y+x}=\dfrac{5}{13+5} \Rightarrow \dfrac{x}{y+x}=\dfrac{5}{18}\\ \\ \\ c)\ \dfrac{x}{y}=\dfrac{5}{13} \Rightarrow\dfrac{y}{x}=\dfrac{13}{5} \Rightarrow \dfrac{y-x}{x}=\dfrac{13-5}{5} \Rightarrow \dfrac{y-x}{x}=\dfrac{8}{5}$