Decagon Side Length Formula:
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The decagon side length formula calculates the length of each side of a regular decagon (10-sided polygon) given its radius (distance from center to vertex).
The calculator uses the decagon side length formula:
Where:
Explanation: The formula derives from dividing the decagon into 10 isosceles triangles and using trigonometric relationships.
Details: Calculating side length is essential in geometry, architecture, and design when working with decagonal shapes. It helps in construction and material estimation.
Tips: Enter the radius of the decagon in any length units. The result will be in the same units. The radius must be a positive number.
Q1: What is a regular decagon?
A: A regular decagon is a 10-sided polygon with all sides equal and all angles equal (144° each).
Q2: What's the difference between radius and apothem?
A: Radius is center-to-vertex distance, while apothem is center-to-side distance. They're related but different measurements.
Q3: Can I calculate the radius if I know the side length?
A: Yes, you can rearrange the formula: \( r = \frac{s}{2 \times \sin(\pi/10)} \).
Q4: What is the exact value of sin(π/10)?
A: \( \sin(\pi/10) = \frac{\sqrt{5} - 1}{4} \approx 0.309016994 \).
Q5: How accurate is this calculation?
A: The calculation is mathematically exact for a perfect regular decagon. Real-world accuracy depends on measurement precision.