Answer:
90km^2
Explanation:
To find the area of the rectangle, multiply it's side lengths together, which are 6 and 12, to get 72. Now, to find the area of a triangle, use this formula. A (area) = b (base) * h (height) / 2. So, we already have the height, which is 6. Notice the top number is the length of the rectangle and the base of the triangle, and we know the length of the rectangle is 12. So, subtract 12 from 18 to get the base of the triangle, which is 6. So, plug this into the formula.
6*6/2
36/2
18
So, now we know the area of the rectangle and triangle, so add them together to get the area of the entire figure: 90.
Don't forget your unit of measurement and that it is squared (because you are dealing with area).