The interior angle of a regular polygon is 156 . How many diagonals does the polygon have ?
(a)60
(b)90
(c)75
(d)120

• ans is 90
  interior angle formula=180*(n-2)/n
  herein,156=180*(n-2)/n
  we get n=15
  number of diagnols=n*(n-3)/2=(15*12)/2=90
• 11 years agoHelpfull: Yes(65) No(1)
• ans is 90 because sides of polygon n =>interior angle of polygon=((n-2)180/n)
  n=15,no diagonal nc2-n=15C2-15=>105-15=>90 ans
• 11 years agoHelpfull: Yes(16) No(2)
• Firstly Calculate the number of sided in the regular polygon which have internal angel is 156.
  Using Formula.
  (n-2)*180=156n
  Which will give value of n as 15
  Now calculate the number of diagonals as (nC2-n)
  Which will give the result as Number of diagonals is 90
• 11 years agoHelpfull: Yes(6) No(1)