document.write( "Question 1194335: The lateral edge of a pyramidal church spire is 92 ft. Each side of its octagonal base is 43 ft.What will be the cost of painting the spire at Php 530.00 a square foot?
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Algebra.Com's Answer #848478 by ikleyn(52781) $\"\"$ $\"About$

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\n" ); document.write( "The lateral edge of a pyramidal church spire is 92 ft.
\n" ); document.write( "Each side of its octagonal base is 43 ft.
\n" ); document.write( "What will be the cost of painting the spire at Php 530.00 a square foot?
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\n" ); document.write( "\n" ); document.write( "        The solution in the post by @proyaop is FATALLY INCORRECT.\r
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\n" ); document.write( "\n" ); document.write( "        It is incorrect, since @proyaop mistakenly treats the lateral edge of the pyramid \r
\n" ); document.write( "\n" ); document.write( "        as its slant height, although (and despite the fact) that they are different conceptions.\r
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\n" ); document.write( "\n" ); document.write( "        I came to bring a correct solution.\r
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document.write( "The perimeter of the pyramidal church spire is p = 43 ft * 8 = 344 ft.\r\n" );
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document.write( "The slant height is  h =  = 89.4525 ft.\r\n" );
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document.write( "The lateral area of the spire is   =  = 15385.83 ft^2.\r\n" );
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document.write( "The cost is  530*15385.83 = Php 8154489.90.    ANSWER\r\n" );
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\n" ); document.write( "\n" ); document.write( "Solved.\r
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\n" ); document.write( "\n" ); document.write( "To check, I calculated the area of one single lateral face as the area of the (92,92,43)-ft
\n" ); document.write( "isosceles triangle using the Heron's formula.\r
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\n" ); document.write( "\n" ); document.write( "I used online calculator https://www.mathopenref.com/heronsformula.html \r
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\n" ); document.write( "\n" ); document.write( "It gave me the area of 1923.2288 ft^2 for one single triangle.\r
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\n" ); document.write( "\n" ); document.write( "For 8 triangles, it gives the total lateral area 1923.2288*8 = 15385.83 ft^2,
\n" ); document.write( "which is the same as in my calculations above.\r
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