Find the number of diagonals that can be drawn by joining the angular ponts of decagon .

Explanation

To find the number of diagonals in a decagon (a polygon with 10 sides), we can use the formula for the number of diagonals in an n-sided polygon:

\[ \text{Number of diagonals} = \frac{n(n-3)}{2} \]

**Step 1: Identify the number of sides (n) in the decagon.**
- A decagon has 10 sides, so we set \( n = 10 \).
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