Answer:
∠A = 60°
∠B = 42°
∠C = 78°
Step-by-step explanation:
∵ In a triangle, sum of all the three interior angles is 180°
∴ m∠A + m∠B + m∠C = 180°
∴ (4x)° + (3x - 3)° + (5x + 3)° = 180°
∴ (4x + 3x - 3 + 5x + 3)° = 180°
∴ (12x)° = 180°
∴ 12x = 180
∴ x = 180/12
∴ x = 15
∠A = (4x)° = (4× 15)° = 60°
∠B = (3x-3)° = (3× 15-3)° =(45-3)°= 42°
∠C = (5x+3)° = (5× 15 + 3)° =(75 + 3)°= 78°
