document.write( "Question 149171: 7. The altitude of a regular triangular pyramid is the segment connecting a vertex to the centroid of the opposite face. A regular triangular pyramid has edges of length 6 inches. How tall is such a pyramid, to the nearest hundredth of an inch? \n" ); document.write( "
Algebra.Com's Answer #109433 by jim_thompson5910(35256)\"\" \"About 
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First let's draw the pyramid (note: my drawings are not to scale).\r
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\n" ); document.write( "\n" ); document.write( "If we just look at the base, we get something like this (Note: The hypotenuse was found through pythagorean's theorem \"sqrt%286%5E2%2B6%5E2%29=sqrt%2836%2B36%29=sqrt%2872%29=6%2Asqrt%282%29\"):\r
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\n" ); document.write( "\n" ); document.write( "Now take half of the hypotenuse to get \"3%2Asqrt%282%29\". This figure will form the leg of the triangle. Now let's one half of a triangular cross section to get this:\r
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\n" ); document.write( "\n" ); document.write( "From the drawing, we can see that legs are \"h\" and \"3%2Asqrt%282%29\" while the hypotenuse is \"6\"\r
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\n" ); document.write( "\n" ); document.write( "So to find \"h\", we need to use pythagorean's theorem:\r
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\n" ); document.write( "\n" ); document.write( "\"a%5E2%2Bb%5E2=c%5E2\"\r
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\n" ); document.write( "\n" ); document.write( "\"h%5E2%2B%283%2Asqrt%282%29%29%5E2=6%5E2\" Plug in \"a=h\", \"b=3%2Asqrt%282%29\", and \"c=6\"\r
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\n" ); document.write( "\n" ); document.write( "\"h%5E2%2B%283%2Asqrt%282%29%29%5E2=36\" Square 6 to get 36.\r
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\n" ); document.write( "\n" ); document.write( "\"h%5E2%2B18=36\" Square \"3%2Asqrt%282%29\" to get \r
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\n" ); document.write( "\n" ); document.write( "\"h%5E2=36-18\" Subtract \"18\" from both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"h%5E2=18\" Combine like terms on the right side.\r
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\n" ); document.write( "\n" ); document.write( "\"h=sqrt%2818%29\" Take the square root of both sides. Note: only the positive square root is considered.\r
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\n" ); document.write( "\n" ); document.write( "\"h=3%2Asqrt%282%29\" Simplify.\r
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\n" ); document.write( "\n" ); document.write( "So the height is \"h=3%2Asqrt%282%29\" or \"h=4.24264\"\r
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\n" ); document.write( "\n" ); document.write( "So the height of the pyramid to the nearest hundredth of an inch is 4.25 inches
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