To solve for its area, we can break the figure apart.
If we splice the figure horizontally, we get a rectangle that is 30 inches long and 18 inches wide and a rectangle that is 30 inches wide and 10 inches in length.
If we solve for the two rectangles separately, we can add them to get the total area of this figure.
The area of rectangle a is 540 sq inches because 30 x 18 = 540.
The area of rectangle b is 300 sq inches because 30 x 10 = 300.
300 + 540 = 840.
The area of this figure is 840 square inches.
Hope this helps! Have an awesome day :)