Answer:
36x² + 24x + 300 ft²
Step-by-step explanation:
→ Area of rectangle = Length × Width
→ Area of rectangle = (12x + 8) ft × (3x + 15) ft
→ Area of rectangle = 12x(3x + 15) + 8(3x + 15) ft²
→ Area of rectangle = 36x² + 180 + 24x + 120 ft²
→ Area of rectangle = 36x² + 24x + 300 ft²
