Question

Calcular o valor de x para cada uma das proporções:
A) 12/3 = 8/x

B) 2 x /15= 6/9

c) (x-2) / x = 4/5

D) (1/3) / (1/5) = 5 / x

E) (x+3) / (X-2) = 3 / 2

F) [1] / [(1/3) + (1/2)] = 2 / x

Answer 1

Boa noite 

A) 12/3 = 8/x

8/x = 4
x = 8/4 = 2 

B) 2x/15 = 6/9

2x/15 = 2/3
2x/5 = 2 
2x = 10
x = 5 

c) (x - 2)/x = 4/5

5x - 10 = 4x
5x - 4x = 10
x = 10

D) (1/3) / (1/5) = 5 / x 

5/3 = 5/x
x = 3 

E) (x + 3) / (x - 2) = 3 / 2 

    2x + 6 = 3x - 6
    x = 12 

F) [1] / [(1/3) + (1/2)] = 2 / x
    
    1/(2/6 + 3/6) = 2/x
    1/(5/6) = 2/x
    6/5 = 2/x 
    6x = 10
    x = 5/3