Respuesta :

Answer:

10

Step-by-step explanation:

The sum of all the interior angles of a pentagon is 540°

So...

540 = 12x + 7x + 16x+ 9x + 10x

Combine like terms:

540 = 12x + 7x + 16x+ 9x + 10x

540 = 54x

Divide by 54 on both sides:

540 = 54x

/54     /54

10 = x

Hope this helps :)