Four angles of a polygon are 100° each. The remaining angles are 160° each. Find the number of sides of the polygon.
A polygon is a closed two-dimensional figure, that comprises three or more straight lines.
Answer: The number of sides of the polygon is 6.
We know that sum of all interior angles of a polygon = (n – 2) × 180°
Explanation:
Let n be the number of sides of the polygon.
The sum of interior angles of the polygon is = (n – 2) × 180° ---- (1)
The number of angles measuring 100° is 4.
The number of angles measuring 160° is n - 4.
So, sum of interior angles of the given polygon = 4 × 100° + (n - 4) × 160°
= (160° × n) - 240° ---- (2)
Equating (1) and (2), we get
(n – 2) × 180° = (160° × n) - 240°
n (180° - 160°) = 360° - 240°
n = 120 / 20
n = 6
Thus the polygon is a hexagon.
Therefore, the number of sides of the polygon is 6 (Hexagon).
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