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It is an octagon with 8 sides.
Let n be the number of sides = number of vertices.
Then each vertex can be connected to n-3 other vertices, giving n(n -3) connections. However, this counts each vertex pair connection twice, so there are:
n(n - 3) / 2 diagonals.
Thus if there are 20 diagonals:
n(n - 3) / 2 = 20
n2 - 3n = 40
n2 - 3n - 40 = 0
(n + 5)(n - 8) = 0
so n = -5 or 8. As a polygon cannot have a negative number of sides, n = 8.
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X plus 20 plus 10x equals 20 plus 9x x equals?
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How do you solve the equation -3x minus 5 equals -20?
Add 5 to both sides of the equation to get rid of the - 5. -3x - 5 + 5 = -20 + 5 Solve and simplify. -3x = -15 Divide both sides of the equation by -3. x = 5
What are the names of the shapes?
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-2x - 14 equals 26?
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If 3 many is a satarday what is 20 many?
3 many =Saturday 3X7 many =21 is also Saturday So 20 many is one day before Friday.
How many diagonals does a 20-sides polygon have?
A polygon with n sides had n*(n-3)/2 diagonals. So a 20 sided polygon would have 20*17/3 = 170
How many sides a polygon with 170 diagonals?
20 sides 1/2*(202-60) = 170 diagonals
What is the total number of diagonals in a polygon with eight sides?
It has 20 diagonals
How many diagonals does a convex polygon with 23 sides have?
A polygon with n sides has n*(n - 3)/2 diagonals. So n = 23 gives 23*20/10 = 230 diagonals
How many sides a polygon has with 10 diagonals?
Such a polygon does not exist. A polygon with n sides has 0.5*n*(n-3) diagonals If there are 10 diagonals then 0.5*n*(n-3) = 10 which requires n2 - 3n - 20 = 0 which has no integer roots.
How many diagonals are in a 20 sided polygon?
There are 170 diagonals
How many diagonals does a 20 gon has?
A 20 sided polygon has 170 diagonals
What type of polygon has 20 diagonals?
A regular octogon (8 sides) has 20 diagonals. An irregular octogon also has 20 diagonals, but only if all its points point outwards.
How many sides and diagonals are there in an octagon?
Sides: 8 Diagonals : 20
How many Diagonals in a 20 sided polygon?
170
How many diagonals does a 12 sided polygon have?
20
How many diagonals can be drawn from any vertex of a 20-sided polygon?
It is 18 diagonals
