Question
Download Solution PDFWhat is the number of diagonals of an octagon?
Answer (Detailed Solution Below)
Detailed Solution
Download Solution PDFConcept:
The no. of diagonals that can be drawn by joining the angular points of a polygon having n sides is given by: \({\;^n}{C_2} - n = \frac{{n \times \left( {n - 3} \right)}}{2}\)
Calculation:
Given: The polygon is an octagon ⇒ The no. of sides of the given polygon n = 8.
As we know that, no. of diagonals that can be drawn by joining the angular points of a polygon having n sides is given by: \({\;^n}{C_2} - n = \frac{{n \times \left( {n - 3} \right)}}{2}\)
⇒ \({\;^8}{C_2} - 8 = \frac{{8 \times 5}}{2} = 20\)Last updated on Jun 18, 2025
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