Question

alguem pode me ajudar por favor ​

Answer 1

F)

$\frac{20}{x + 1} = \frac{16}{x} \\ 20x = 16(x + 1) \\ 20x = 16x + 16 \\ 20x - 16x = 16 \\ 4x = 16 \\ x = \frac{16}{4} \\ x = 4$

G)

$\frac{3}{2} = \frac{x + 3}{x - 1} \\ 3(x - 1) = 2(x + 3) \\ 3x - 3 = 2x + 6 \\ 3x - 2x = 6 + 3 \\ x = 9$

H)

$\frac{ \frac{2}{3} }{x} = \frac{7}{5} \\ \frac{2}{3} \times \frac{1}{x} = \frac{7}{5} \\ \frac{2}{3x} = \frac{7}{5} \\ 21x = 10 \\ x = \frac{10}{21}$

I)

$\frac{10}{ \frac{5}{4} } = \frac{x}{ \frac{1}{2} } \\ \frac{10}{1} \times \frac{4}{5} = \frac{x}{1} \times \frac{2}{1} \\ \frac{40}{5} = \frac{2x}{1} \\ 10x = 40 \\ x = \frac{40}{10} \\ x = 4$

J)

$\frac{1}{ \frac{1}{2} + \frac{1}{3} } = \frac{2}{x} \\ \frac{1}{3 + 2} = \frac{2}{x} \\ x = 2(3 + 2) \\ x = 6 + 4 \\ x = 10$