KCET · Maths · Permutation Combination
The number of diagonals that can be drawn in an octagon is
- A \(15\)
- B \(20\)
- C \(28\)
- D \(30\)
Answer & Solution
Correct Answer
(B) \(20\)
Step-by-step Solution
Detailed explanation
A octagon has 8 sides.
\(\rightarrow\) The number of diagonals in a polygon is \(\frac{\mathrm{n}(\mathrm{n}-3)}{2}\), Where n is the number of sides.
\(\rightarrow \frac{8(8-3)}{2}=4.5=20\)
\(\rightarrow\) The number of diagonals in a polygon is \(\frac{\mathrm{n}(\mathrm{n}-3)}{2}\), Where n is the number of sides.
\(\rightarrow \frac{8(8-3)}{2}=4.5=20\)
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