Engineering Board Exam Reviewer · Polygons · easy
How many diagonals does a decagon have?
- 35
- 45
- 70
- 20
Answer
A. 35
Solution
n(n-3)/2=10(7)/2=35.
More Polygons questions
- Find the measure of each exterior angle of a regular octagon.
- Find the sum of the interior angles of a hexagon.
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- Find the number of diagonals in a regular polygon with 15 sides.
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- Find the area of a regular hexagon with side length 8 cm.
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- A regular hexagon is inscribed in a circle of radius 8. Find the area inside the circle but outside the hexagon.