document.write( "Question 197513: Hello.\r
\n" ); document.write( "\n" ); document.write( "Find the length of a diagonal of a cube that has edges of length 6 in.\r
\n" ); document.write( "\n" ); document.write( "I though I could use $\"+a%5E2+%2B+b%5E2+=+c%5E2+\"$ (i.e. $\"+36%2B36=c%5E2+=+8.485\"$ ) but sheet says the answer is 10.3923 NOT 8.485. can someone please help.
\n" ); document.write( "thanks. \n" ); document.write( "

Algebra.Com's Answer #148106 by Alan3354(69443) $\"\"$ $\"About$

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Find the length of a diagonal of a cube that has edges of length 6 in.\r
\n" ); document.write( "\n" ); document.write( "I though I could use $\"+a%5E2+%2B+b%5E2+=+c%5E2+\"$ (i.e. $\"+36%2B36=c%5E2+=+8.485\"$ ) but sheet says the answer is 10.3923 NOT 8.485
\n" ); document.write( "------------------
\n" ); document.write( "That, 8.485, is the diagonal on one of the faces, from corner to corner.
\n" ); document.write( "For a cube's diagonal from opposite vertices, it's
\n" ); document.write( "d^2 = a^2+b^2+c^2, or 3*6^2 since all edges are 6 inches.
\n" ); document.write( "d^2 = 108
\n" ); document.write( "d = ~ 10.3923 \n" ); document.write( "

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