Question

1. Calcule o valor de x em cada item.

Answer 1

a)
$\frac{3}{4} = \frac{x}{6}$
aí vc multiplica cruzado
$3 \times 6 = 18 \\ 4 \times x = 4x$
$4 x = 18 \\ x \frac{18}{4} = \frac{9}{2}$
$\frac{9}{2} + \frac{5}{2} = \frac{9 + 5}{2} = \frac{14}{2} = 7$

b)
$\frac{x}{3} = \frac{2x}{9}$
$3 \times x = 3x \\ 2x \times 9 = 18x$
$18x + 3x = 6 \times \\ x = 6$
$6 - 1 = 5 \\ 2 \times 6 = 12$