Respuesta :

Answer:

Ima guess 60

Step-by-step explanation:

9514 1404 393

Answer:

  60°

Step-by-step explanation:

The exterior angle is equal to the sum of the remote interior angles:

  100° = 40° +∠B

  60° = ∠B . . . . . . . . . . . . . subtract 40° from both sides