please help it’s due in 30 minutes

Answer:
Step-by-step explanation:
Area of a right angled triangle = Base x Height x 0.5
Base = 3
Height = 12
Area of a right angled triangle = 3 x 12 x 0.5
Area of a right angled triangle = 36 x 0.5
Area of a right angled triangle = 18 inches²