Find the area of the polygon shown. Enter the number into the box.
ft? 1 ft 4 ft 4 ft

The area of the trapezium is 18 ft²

Step-by-step explanation:

Given;

Two parallel sides of the polygon as  follows;

The first parallel side = 1 ft + 4 ft = 5 ft

The second parallel side = 4 ft

If this polygon is rotated 90 degrees, it forms a trapezium with a height of 4 ft.

The area of a trapezium is calculated as;

Therefore, the area of the trapezium is 18 ft²