Estimate the area of the irregular shape. Explain your method and show your work. Can someone explain this to me?

Answer:
Approximate area: 27.5 square units
Step-by-step explanation:
The irregular shape is very similar to a trapezium with coordinates (-3,3), (2, 2), (2, -2) and (-3, -4).
Area of a trapezium: [(a+ b)/2]*h
where a and b refer to the two parallel sides and h is the distance between them. From the above coordinates: a = 7 length units, b = 4 length units and h = 5 length units. Therefore, approximate area = [(7+ 4)/2]*5 = 27.5 square units