Its an isosceles triangle and just for future reference, you can google the types of triangles and you will find websites with definition and answers
The sum of the interior angles of a polygon with 
sides is
Since a pentagon has 5 sides, the sum of its interior angles is
Since it is a regular pentagon, all sides and angles are the same, so one single angle measures
degrees.
The exclamation points mean factorial which is when you multiply that number along with the numbers less than it. Ex: 4! = 4*3*2*1. To solve this, you must get those factorials and after you solve, you get 60480
200 divided by 5 equals 40.
So therefore, 40 times 5 equals 200.
I should say that 13, 24, 14 are the next three numbers, because as you can see above the first(11) number is the third(12) number minus 1 and the fourth(23) is the second (22) plus 1 if you understand what I`m trying to say
