Final answer:
The area of the lawn shaped like a trapezoid is 264 square meters.
Step-by-step explanation:
To find the area of the lawn shaped like a trapezoid, we use the formula for the area of a trapezoid: Area = ((a+b)/2) * h, where a and b are the lengths of the parallel sides of the trapezoid, and h is the height. In this case, a = 18 m, b = 4 m, and h = 12 m.
Plugging in the values, we get: Area = ((18+4)/2) * 12 = 22 * 12 = 264 m².
Therefore, the area of the lawn is 264 square meters.