If you take 1 vertex of your 12-gon and draw lines (excluding the lines from the vertex you have chosen) to the 10 other vertices you get 10 triangles. Each triangle has 180 degrees.
The total number of degrees in the interior of the 12-gon is 180 * 10 = 1800
For this problem you are given the vertical and horizontal sides of the triangle. The flagpole (6.5 meters) is the up-and-down triangle side and the distance from the hook to the flagpole is the base (5.2 meters) of the triangle.
He needs $100 for the new bike but already has the $28 so you also have to add 12x because thats what you need to find. X represents the amount of days he has to work.
