Two intersecting lines create four angles with the same vertex, labeled A , B , C , and D . Angle B is adjacent to ∠A and ∠C . Find m∠A if m∠C=75° .(1 point) Responses 105° 105 degrees 180° 180 degrees 75° 75 degrees 15°
Since angles A and C are adjacent and share a common vertex, their sum must be equal to 180°.
m∠A + m∠C = 180°
m∠A + 75° = 180°
Subtract 75° from both sides:
m∠A = 180° - 75°
m∠A = 105°
Therefore, the measure of angle A is 105°.