Question

12. A long time ago Dulani found an island shaped like a triangle with three straight shores of length 3 km, 4 km and 5 km. He said nobody could come within 1 km of his shore. What was the area of his exclusion zone?​

Answer 1

Відповідь:

15.14 sq.km

Пояснення:

Dimensions 3km, 4km and 5km are pythagorean triplets, ie, the island is right triangle

shaped.

If you take 1km offshore the island, you will have three rectangles of dimensions

(5km,1km), (4km,1km), (3km,1km) and a complete circle of radius 1km.

Thus, the area of exclusion zone = sum of the areas of three rectangles + area of circle

= 5x1 + 4x1 + 3x1 + 3.14x1

= 15.14 sq.km