A right triangle. Hope this helps.
Step-by-step answer:
This is a regular heptagon, means it has 7 <em>congruent</em> sides and 7 <em>congruent </em>vertex angles.
To work with polygons, there is a very important piece of information that you must know to solve the majority of related problems.
This is:
sum of exterior angles of polygons = 360 degrees.
If you don't remember the 360 degrees, think of the sum of exterior angles of an equilateral triangle, which is 3*(180-60)=3*120=360! It works!
For a regular heptagon, c = 360/7=51.43 degrees approx.
This means that each vertex angle measures
vertex angle = 180-c
So since 2d+the vertex angle = 360, we have
2d+(180-c)=360
solve for d:
2d=360-(180-c)=180+c
d=(180+c)/2=90+c/2=115.71 degrees. (approx.)
Answer:
Total number of milkshakes sold on Monday = 300
Number of milkshakes without whipped cream = 90
Step-by-step explanation:
Given:
Adrienne adds whipped cream to 210 milk shakes which is 70% of the total milk shakes sold.
To find the total milkshakes sold.
Solution:
Let the total number of milkshakes sold on Monday be = 
Percentage of milkshakes with whipped cream added to them = 70%
Number of milk shakes with added whipped cream can be given as:
⇒ 
⇒ 
⇒
[Representing percent in fraction form]
⇒
[evaluating in decimals]
We know that the number of milkshakes with whipped cream added to them = 210.
So, we have:

Solving for 
Dividing both sides by 0.7

∴ 
Thus, total number of milkshakes sold on Monday = 300
Number of milkshakes without whipped cream =
= 90