Its the first one, 22.5. This is because... if you multiply 5 and 4, you would get 20, the area of the square. You then have to multiply 1 and 5 to get 5 and divide it by 2 to get the area of the triangle which would be 2.5, then add 2.5 to 20 and get 22.5. Hope this helps :)
Explanation: The total area can be calculated by summing the areas of the rectangle and the triangle.
1- getting the area of the rectangle: area of square = length * width In the given, we have: length = 4 ft width = 5 ft Therefore: area of rectangle = 4 * 5 = 20 ft²
2- getting the area of the triangle: area of triangle = 0.5 * base * height In the given, we have: base = 5 ft height = 1 ft Therefore: area of triangle = 0.5 * 5 * 1 = 2.5 ft²
3- getting the total area: Total area = area of rectangle + area of triangle Total area = 20 + 2.5 = 22.5 ft²