The first thing we must do for this case is to define variables.
We have then:
x: unknown number
We now write the equation that models the problem:
[tex] 2x + 8 = x + 12
[/tex]
From here, we clear the value of x.
[tex] 2x - x = 12 - 8
x = 4
[/tex]
The unknown number is equal to 4.
Answer:
The number is:
[tex] x = 4 [/tex]
