Answer:
18
Step-by-step explanation:
Let
S = sum of the measures of the interior angles of a polygon
n = number of sides of a polygon
The equation is
S = (n - 2) * 180°
Where,
S = 2,880°
S = (n - 2) * 180°
2,880° = (n - 2) * 180°
2,880° = 180°n - 360°
2,880° + 360° = 180°n
3,240° = 180°n
Divide both sides by 180°
n = 3,240° / 180°
n = 18
