Answer:
a
Step-by-step explanation:
The area (A) of a triangle is calculated as
A = [tex]\frac{1}{2}[/tex] bh ( b is the base and h the perpendicular height )
Here b = 9 and h = 12 , then
A = [tex]\frac{1}{2}[/tex] × 9 × 12 = [tex]\frac{1}{2}[/tex] × 108 = 54 cm²
