WILL MARK BRAINLIEST!!!!!!MUST BE CORRECT!

Hi there! The answer is 9 square units

To find the area of a triangle we use the following formula:
Area = 0.5 * base * height.

The base of this triangle:
AC = 6 

The height of this triangle:
BD = 3

Filling in this formula gives us: 
Area = 0.5 * 3 * 6 = 9

Therefore, the answer is 9 square units