Answer:
The area of the polygon is 92.75 cm^2
Explanation:
To find the area of the polygon, we simply add up the areas of the constituent triangles
At any point in time;
Area of a triangle = 1/2 * base * height
So we proceed as follows;
(1/2 * 12 * 4.5) + (1/2 * 12 * 5)
= 27 + 30 = 57 cm^2
There is a last triangle with 12 cm and 5 cm as the sides and we need the length of the hypotenuse
The length of the hypotenuse for that triangle will be 13 cm. This is because 5,12 and 13 are Pythagorean triple and they form the sides of a right-angled triangle
So for the last triangle, the area will be;
1/2 * 13 * 5.5 = 35.75 cm^2
So the total area is;
35.75 + 57 = 92.75 cm^2