use the relationship between supplemantary angles a and b what is m a if m b = 121
Since supplementary angles add up to 180 degrees, we can use the relationship between angles a and b to determine the measure of angle a.
If angle b (m b) = 121 degrees, then angle a must be:
m a = 180 - m b
m a = 180 - 121
m a = 59
Therefore, the measure of angle a is 59 degrees.