Question

Determine o valor de x nas proporções:

Answer 1

Oiee, como vai? Já se hidratou hj? :3

=> Resposta:

$a) \\ \frac{2}{x + 1} = \frac{1}{5} \\ \\ 1 \times (x + 1) = 10 \\ x + 1 = 10 \\ x = 10 - 1 \\ x = 9$

$b) \\ \frac{2}{9} = \frac{x + 1}{18} \\ \\ 9 \times (x + 1) = 36 \\ 9x + 9 = 36 \\ 9x = 36 - 9 \\ 9x = 27 \\ \\ x = \frac{27}{9} \\ x = 3$

$c) \\ \frac{4}{3x + 2} = \frac{1}{2} \\ \\ 1 \times (3x + 2) = 8 \\ 3x + 2 = 8 \\ 3x = 8 - 2 \\ 3x = 6 \\ x = \frac{6}{3} \\ x = 2$

$d) \\ \frac{5x - 3}{ 14} = \frac{1}{2} \\ \\ 2 \times (5x - 3) = 14 \\ 10x - 6 = 14 \\ 10x = 14 + 6 \\ 10x = 20 \\ x = \frac{20}{10} \\ x = 2$

$e) \\ \frac{3x}{4} = \frac{x + 3}{2} \\ \\ 4 \times (x + 3) = 6x \\ 4x + 12 = 6x \\ 4x = 6x - 12 \\ 4x - 6x = - 12 \\ - 2x = - 12 \\ x = \frac{ - 12}{ - 2} \\ x = 6$

$f) \\ \frac{x + 3}{3} = \frac{20}{6} \\ \\ 6 \times (x + 3) = 60 \\ 6x + 18 = 60 \\ 6x = 60 - 18 \\ 6x = 42 \\ x = \frac{42}{6} \\ x = 7$

$g) \\ \frac{x + 7}{21} = \frac{4}{7} \\ \\ 7 \times (x + 7) = 84 \\ 7x + 49 = 84 \\ 7x = 84 - 49 \\ 7x = 35 \\ x = \frac{35}{7} \\ x = 5$

$h) \\ \frac{x - 2}{x + 1} = \frac{1}{2} \\ \\ 2 \times (x - 2) = 1 \times (x + 1) \\ 2x - 4 = x + 1 \\ 2x = x + 1 + 4 \\ 2x - x = 1 + 4 \\ x = 5$

=> Espero ter ajudado, bom estudo! <3