Question

calcule o valor de x nas proporções a seguir :

A) X/6 = x+3/15


B) X-2/x = 12/20



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Answer 1

$> resolucao \\ \\ \\ > \frac{x}{6} = \frac{x + 3}{15} \\ \\ > 15x = 6x + 18 \\ \\ > 15x - 6x = 18 \\ \\ 9x = 18 \\ \\ x = \frac{18}{9} \\ \\ x = 2 \\ \\ \\ - - - - - - - - - - - - - - \\ \\ \\ > \frac{x - 2}{x} = \frac{12}{20} \\ \\ > 20x - 40 = 12x \\ \\ 20x - 12x = 40 \\ \\ 8x = 40 \\ \\ x = \frac{40}{8} \\ \\ x = 5 \\ \\ \\ > > > > > > > >$

Answer 2

Explicação passo-a-passo:

a)

$\dfrac{x}{6} = \dfrac{x + 3}{15}$

Multiplique cruzado.

$6(x + 3) = 15x$

$6x + 18 = 15x$

$6x - 15x = - 18$

$- 9x = - 18$

$x = \dfrac{ - 18}{ - 9}$

$x = 2$

b)

$\dfrac{x - 2}{x} = \dfrac{12}{20}$

Multiplique cruzado

$20(x - 2) = 12x$

$20x - 40 = 12x$

$20x - 12x = 40$

$8x = 40$

$x = \dfrac{40}{8}$

$x = 5$