Respuesta :

There is 4 X so you use 360- (11+1) which is 348 and now divide by 4 which is now 87

Thank you for asking

From Cambridge

Answer:

42

Step-by-step explanation:

3x+1+x+11 = 180

4x+12 = 180

4x= 180-12

4x=168

x = 168/4

x = 42