Recall that the sum of the interior angles of a convex polygon with n sides is:
Therefore:
12) If the sum of the interior angles of a convex polygon is 3240 degrees, then we can set the following equation:
Dividing the above equation by 180 we get:
Adding 2 to the above equation we get:
13) If the sum of the interior angles of a convex polygon is 6660 degrees, then we can set the following equation:
Dividing the above equation by 180 we get:
Adding 2 to the above equation we get:
Answer:
12) 20.
13) 39.