Question

10 12
____ = ___
×+10 2×

use a propriedade e proporcao calcule o valor das incognitas em cada item

Answer 1

10.2x=12(x+10)
20x=12x+120
20x-12x=120
8x=120
x=120/8
x=15

Answer 2

  10             12
---------   =  --------
x + 10          2x

10.2x = 12.(x + 10)

20x = 12x + 120

20x - 12x = 120

8x = 120

x =  120 
       -------
          8

x = 15