Respuesta :

Let x = 1st integer
    x + 1 = 2nd integer
    x + 2 = 3rd integer
3(x + x + 2) = 12(x + 1) - 84
3(2x + 2) = 12x + 12 - 84
6x + 6 = 12x - 72
-6x = -78
x = 13
Answer: 13, 14, 15