Use the relationship between supplementary angles ∠a and ∠b . What is m∠a if m∠b=121° ?(1 point) Responses

If the angles ∠a and ∠b are supplementary, it means that the sum of the measures of the two angles is 180°.

Therefore, if m∠b = 121°, we can find m∠a by subtracting m∠b from 180°:

m∠a = 180° - m∠b
m∠a = 180° - 121°
m∠a = 59°