The answer is 11 can someone tell me why?
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Answer:
The sum of interior angles is found by using the following equation:
∑ of interior angles = (S - 2)180
S = sides.
Note that the sum is given to you, or 1620. Plug in 1620 for the sum:
1620 = (S - 2)180
Next, isolate the variable, s. Note the equal sign, what you do to one side, you do to the other. Divide 180 from both sides:
(1620)/180 = ((S - 2)180)/180
S - 2 = 1620/180
S - 2 = 9
Next, isolate the variable, s. Add 2 to both sides:
S - 2 (+2) = 9 (+2)
S = 9 + 2
S = 11
~
Step-by-step explanation:
to find the interior angles of a polygon, you must figure out 2 things: the number of angles, and what each measures
since there is 1620 for the angles and (n-2)180 = sum of int. angles, we can solve using this (n = the number of sides)
(n-2)180 = 1620
180n - 360 = 1620
180n = 1620 + 360
180n = 1980
1980/180 = n
n = 11 sides