The area \( A \) of a triangle can be calculated using the formula:
\[ A = \frac{1}{2} \times \text{base} \times \text{height} \]
For the given triangle:
- Base = 9 feet
- Height = 12 feet
Plugging in the values:
\[ A = \frac{1}{2} \times 9 \times 12 \]
Calculating the area:
\[ A = \frac{1}{2} \times 9 \times 12 = \frac{1}{2} \times 108 = 54 \text{ ft}^2 \]
Thus, the area of the triangle is \( 54 \text{ ft}^2 \).