Respuesta :

Answer:

x=28°

Step-by-step explanation:

supplementary angles equal 180°

So:

3x+2x+x+12=180°

6x+12=180

6x=168

x=28°

Therefore:

3x:

3(28)=84°

2x:

2(28)=26°

x+12:

28+12=40°