Respuesta :

Answer:

45°

Step-by-step explanation:

Angles in a triangle add to 180 degrees, so

  • 2x - 12 + 2x + 17 + 9x - 7 = 180
  • 13x - 2 = 180
  • 13x = 182
  • x = 14

So, the measure of angle X is 2(14)+17=45°