Respuesta :

Answer:

  14

Step-by-step explanation:

The applicable rule of exponents is ...

  (a^b)(a^c) = a^(b+c)

__

You have ...

  (x^3)(x^a) = x^17

  x^(3+a) = x^17

Equating exponents, we get ...

  3 +a = 17

  a = 14

The missing exponent is 14.