Answer:
122°
Step-by-step explanation:
triangle = 180°
∴180 - 43 - 15
=122°
The Angle Sum Property of a triangle gives that the sum of the internal angles of a triangle is equal to 180°.
Hence,
⇒ ∠A + ∠B + ∠C = 180°
⇒ ∠A + 43° + 15° = 180°
⇒ ∠A + 58° = 180°
⇒ ∠A = 122°
