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A polyhedron has 2 hexagonal faces and 12 triangular faces. How many vertices does it have?

1 Answer

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Answer:

12 vertices

Explanation:

Euler's formula is:

F + V = E + 2

(faces + vertices = edges + 2)

SInce we are missing the number of vertices, we'd need to solve for V. The base equation looks like this:

(12+2) + V = {(3* 12 + 2*6) /2} + 2

We have 12 traingular faces and 2 hexagonal faces, which together equal 14 faces. Equation now looks like this:

14 + V = {(3* 12 + 2*6) /2} + 2

Moving on to the number of edges, we have 12 triangles. Triangles have three sides, so the number of sides as a result of the triangles would be 3*12, which equals 36.

There are also 2 hexagons, which have 6 sides. 6*2 is 12, add it to 36 to get the total sides in the figure and you get 48. Since edges = sides/2, we devide 48 bu 2 to get 24. There are 24 edges in this figure. Here is how our equation looks now:

14 + V = 24 + 2

Now we simply combine like terms.

14 + V = 24 + 2

14 + V = 26

V = 26 - 14

V = 12

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