document.write( "Question 1141737: Use Euler’s Formula to find the number of vertices in the polyhedron with 11 faces, 1 decagon, and 10 triangles.
\n" ); document.write( "a. 11
\n" ); document.write( "b. 22
\n" ); document.write( "c. 6
\n" ); document.write( "d. 10
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Algebra.Com's Answer #762359 by greenestamps(13200)\"\" \"About 
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\n" ); document.write( "Euler's Formula: F - E + V = 2.

\n" ); document.write( "The polyhedron has 11 faces -- that is given.

\n" ); document.write( "The polyhedron has one decagon face and 10 triangle faces. That is 10+10(3) = 40 edges. An edge of the polyhedron is where 2 polygon edges meet; so the number of edges of the polyhedron is 40/2 = 20.

\n" ); document.write( "Then

\n" ); document.write( "\"11+-+20+%2B+V+=+2\"
\n" ); document.write( "\"V+=+11\"

\n" ); document.write( "The polyhedron has 11 vertices.

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\n" ); document.write( "While Euler's Formula is useful for solving many problems, it is not needed here. A little thinking shows that the polyhedron is a pyramid with a decagon for a base. The base has 10 vertices; the peak of the pyramid is the only other vertex.

\n" ); document.write( "10+1 = 11 vertices.
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