Answer:
D=27 units, E=21 units, F=24 units
Explanation:
The formula for area of a triangle is (BASE * HEIGHT)/2
For triangle D, the base is 9 units and the height is 6 units. Then you can apply the formula and do 9*6 which is 54 and then do 54/2 which is 27 units.
Similarly, the base for E is 6 units, and the height is 7 units. So you do 6*7 which is 42 and then do 42/2 which is 21 units.
Again, the base for F is 6 units, and the height is 8 units. Then again, using the formula, we can do 6*8 which is 48 and then do 48/2, which is 24 units.
Hopefully this helped!