Question

Razao e proporcao, me ajudem please
x/y = 3/4 e x+y=21

Answer 1

$\frac{x}{y} = \frac{3}{4} \\ \frac{x + y}{x} = \frac{3 + 4}{3} \\ \frac{21}{x} = \frac{7}{3} \\ 7x = 63 \\ x = \frac{63}{7} \\ x = 9$

Substituindo esse valor de x:

$x + y = 21 \\ 9 + y = 21 \\ y = 21 - 9 \\ y = 12$


Logo, x = 9 e y = 12.