first you can find angle C:
A - 50 ⇒ 75 - 50 = 25°
should know if you add all the angles in the triangle together you will always get 180 °
so now you can find angle B:
180- ( 75 + 25 ) ⇒ 180- ( 100 ) = 80°
so the measure of angle A is: 75°
the measure of angle B is: 80°
the measure of angle C is: 25°
i hope this is helpful
have a nice day
