Respuesta :

3x+12x+5x=180
20x=180
X=9

Answer:

angle 1 = 3x = 27

angle 2 = 5x = 45

angle 3 = 12x = 108

Step-by-step explanation:

12x + 5x + 3x = 180 .........                            (angle sum property)

20x = 180

x = 180/20 = 9

angle 1 = 3x = 27

angle 2 = 5x = 45

angle 3 = 12x = 108

I hope im right!!