Respuesta :

Answer:

x = 8.5

Step-by-step explanation:

You have all three angles already, so it's easy: 90°, (4x - 8)°, (6x + 13)°

The sum of all angles is 180°

90 + (4x - 8) + (6x + 13) = 180

10x + 95 = 180

      - 95     -95

10x = 85

x = 8.5