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The formula for the number of diagonals (that is, lines joining non-adjacent vertices) belonging to any shape is n(n-3)/2. Therefore, an eighteen-sided polygon has 18 x (18 - 3)/2 = 135 diagonals.
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How many sides does an octadecagon have?
An octadecagon, also called an octakaidecagon, has 18 sides, from the Greek octa-, signifying 8, the connector -kai-, and deca- signifying 10.
How many diagonals does a undecagon have?
A undecagon has 44 diagonals. A dodecagon has 54 diagonals. An octagon has 20 diagonals. A heptagon has 14 diagonals.
How many diagonals does a quadrilateral?
2 diagonals
How many diagonals does a square have?
It has 2 Diagonals!!!
How many diagonals has a nonagon have?
It has 27 diagonals
What regular polygon has 9 diagonals?
A regular octadecagon (an eighteen sided polygon) would have nine diagonals.
How many faces does a octadecagon?
An octadecagon is an 18 sided polygon.
How many vertices does a octadecagon have?
It has 18
How many sides does an octadecagon have?
An octadecagon, also called an octakaidecagon, has 18 sides, from the Greek octa-, signifying 8, the connector -kai-, and deca- signifying 10.
How many diagonals does triacontakaihexagon has?
It has 1,345,890 diagonals
How many diagonals does a undecagon have?
A undecagon has 44 diagonals. A dodecagon has 54 diagonals. An octagon has 20 diagonals. A heptagon has 14 diagonals.
How many diagonals in nonagon?
24 diagonals
How many diagonals does a quadrilateral?
2 diagonals
How many diagonals does a square have?
It has 2 Diagonals!!!
How many diagonals are in a octagon?
There are 20 diagonals
How many diagonals do octagons have?
20 diagonals
How many diagonals has a nonagon have?
It has 27 diagonals
