Respuesta :

bakershawn04

Answer:

B. 90

Step-by-step explanation:

Since the two angles are supplementary, this means they both are on a flat line (180 degrees)

Since both A and B add up to 180, we take that number and subtract A (90) to get our answer: 90 degrees

B.90 if angles are supplementary that means they add up to 180 degrees and 90 plus 90 is 180