Question

determine x nas proporções abaixo:
a) 3/x = 8/20
b) 3x/x-6 = 5/2
c) x+6/x+10 = 4/5

Answer 1

Resposta:

Explicação passo-a-passo:

a) 3/x = 8/20

   x    =  3 . 20/8

   x    =  7,5

b) 3x/6 - x = 5/2

   3x = 5/2 . (6 - x)

   3x = 30/2 - 5x/2

   3x . 2 = 30 - 5x

   6x + 5x = 30

   11x = 30

   x = 30/11

   x = 2,72

c) x + 6/ x + 10 = 4/5

   x + 6 = 4/5 . (x + 10)

   x + 6 = 0,8x + 8

   x - 0,8x = 2

   0.2x = 2

   x = 2/0,2

   x = 10

   

Answer 2

Olá! Tudo bem? :)

a) 3/x = 8/20

$\frac{3}{x} = \frac{8}{20}$

8 × x = 3 × 20

8x = 60

x = 60/8 = $\frac{60}{8}$

x = 7,5

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b)3x/x-6 = 5/2

$\frac{3x}{x-6} = \frac{5}{2}$

3x × 2 = x - 6 × 5

6x = 5x - 30

6x - 5x = -30

x = -30

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c)x+6/x+10 = 4/5

$\frac{x+6}{x+10} = \frac{4}{5}$

x+10 × 4 = x+6 × 5

4x+40 = 5x+30

4x - 5x = 30 - 40

-x = 10 ×(-1)

x = -10

ESPERO TER AJUDADO!!