Respuesta :

Answer:

m∠A = 49°

Step-by-step explanation:

According to Angle Sum Property,

  • angles of the Δ add up to 180°
  • ∠A + ∠B + ∠D = 180°
  • 5x - 6 + 7x - 24 + 78 = 180
  • 12x + 48 = 180
  • x + 4 = 15
  • x = 11

m∠A

  • 5x - 6
  • 5(11) - 6
  • 55 - 6
  • 49°