ANSWER
230 square miles
Step-by-step explanation
We can divide this figure as shown in the picture: 2 rectangles and a right triangle. We find the area of each figure and then we add them up.
One of the rectangles's length is 5 mi and its width is 14 mi. Its area is:
The other rectangle's lenght is 10mi and its width is 5mi. Its area is:
The triangle height is:
And its base is 10mi. Its area is:
The area of the figure is: