As shown in the figure, we know that the triangle rolled twice, and the first roll was 180-60= 120 degrees, that is, it turned 120 degrees with the triangle side length as the radius. The length of point A is 2 * 2 * 3.14 * 6 * (120/360) = 25.12cm.

From the triangle area of 15cm, the square of the triangle side length can be calculated as 20√3, so the swept area is 2 * 3.14 * 20 √ 3 * (120/360)+15 =15.