Question

urgent!! dau coroana!!​

Answer 1

Explicație pas cu pas:

$\dfrac{x}{y} = \dfrac{4}{5}$

a)

$\dfrac{x + y}{y} = \dfrac{4 + 5}{5} \iff \dfrac{x + y}{y} = \dfrac{9}{5}$

b)

$\dfrac{x}{y + x} = \dfrac{4}{5 + 4} \iff \dfrac{x}{y + x} = \dfrac{4}{9}$

c)

$\dfrac{x}{y} = \dfrac{4}{5} \iff \dfrac{y}{x} = \dfrac{5}{4}$

$\dfrac{y - x}{x} = \dfrac{5 - 4}{4} \iff \dfrac{y - x}{x} = \dfrac{1}{4}$