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- Fix the shape.
- Choose the matching formula.
- Substitute values with units.
Correct Answer: C
Correct Answer: C
Method / Topic: Geometry
The answer uses the formula that matches the figure and target quantity.
Short Explanation
Detailed Explanation
Correct Answer: C
Method / Topic: Geometry
<table cellspacing="0" style="border-collapse:collapse; height:20px; width:85px">
<tbody>
<tr>
<td style="border-bottom:none; border-left:none; border-right:none; border-top:none; height:20px; vertical-align:top; white-space:normal; width:85px"><span style="color:#000000">For an n-sided polygon, diagonals=n(n-3)/2. With n=10, the count is 10×7/2=35.</span></td>
</tr>
</tbody>
</table>
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Learn + Solve: Shortcut, Trap & Fast Route Click to view shortcut, steps, and common mistake
Shortcut used, common trap, and the fastest solving route
- Fix the shape.
- Choose the matching formula.
- Substitute values with units.
How many diagonals does a decagon have?
Explanation
Correct Answer: C
Method / Topic: Geometry
The answer uses the formula that matches the figure and target quantity.
Short Explanation
Detailed Explanation
Correct Answer: C
Method / Topic: Geometry
<table cellspacing="0" style="border-collapse:collapse; height:20px; width:85px">
<tbody>
<tr>
<td style="border-bottom:none; border-left:none; border-right:none; border-top:none; height:20px; vertical-align:top; white-space:normal; width:85px"><span style="color:#000000">For an n-sided polygon, diagonals=n(n-3)/2. With n=10, the count is 10×7/2=35.</span></td>
</tr>
</tbody>
</table>
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