Respuesta :
Let's say David's age right now is x years
x + 6 = 2(x - 7)
x + 6 = 2x - 14
x = 20
Therefor David is 20 years old
x + 6 = 2(x - 7)
x + 6 = 2x - 14
x = 20
Therefor David is 20 years old