I need help with problem 19
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Answer:
24
Step-by-step explanation:
The formula for calculating the sum of interior angles is:
(n - 2) x 180° (where n is the number of sides)
interior angle of a polygon = sum of interior angles ÷ number of sides
165 = [ (n - 2) x 180° ] ÷ n
Mulitply both sides by n: 165n = (n - 2) x 180°
Expand brackets: 165n = 180n - 360
Add 360 to both sides: 165n + 360 = 180n
Subtract 165n from both sides: 360 = 15n
Divide both sides by 15: 24 = n
Therefore, the number of sides = 24