Respuesta :

faelure

Answer: x=9

Step-by-step explanation:

Every internal angle within a triangle produces a sum of 180. Therefore we can make this equation:

180-(12x+13)+8x-3+52=180

From there we just solve step by step.

-12x-13+8x-3+52=0

-4x+36=0

-4x=-36

x=9