document.write( "Question 314267: Solve for the indicated letter. Solve the formula.\r
\n" ); document.write( "\n" ); document.write( " S= 1/3 nr^2h + 4nrh for r.
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Algebra.Com's Answer #225254 by ankor@dixie-net.com(22740)\"\" \"About 
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Solve for the indicated letter. Solve the formula.
\n" ); document.write( "S = \"1%2F3\"\"nr%5E2h+%2B+4nrh\" for r.
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\n" ); document.write( "\"1%2F3\"\"nr%5E2h+%2B+4nrh\" = S
\n" ); document.write( "Multiply by 3
\n" ); document.write( "\"nr%5E2h+%2B+3%284nrh%29\" = 3S
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\n" ); document.write( "\"nr%5E2h+%2B+12nrh\" = 3S
\n" ); document.write( "Factor out nh
\n" ); document.write( "nh(r^2 + 12r) = 3S
\n" ); document.write( "divide both sides by nh
\n" ); document.write( "r^2 + 12r = \"%283S%29%2F%28nh%29\"
\n" ); document.write( "Arrange as a quadratic equation
\n" ); document.write( "r^2 + 12r - \"%283S%29%2F%28nh%29\" = 0
\n" ); document.write( "Solve for r using the quadratic formula
\n" ); document.write( "\"x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+\"
\n" ); document.write( "In this equation: x = r a=1; b=12; c=-\"%283S%29%2F%28nh%29\"
\n" ); document.write( "\"r+=+%28-12+%2B-+sqrt%2812%5E2-4%2A1%2A%28%28-3S%29%2F%28nh%29%29+%29%29%2F%282%2A1%29+\"
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\n" ); document.write( "\"r+=+%28-12+%2B-+sqrt%28144-4%28%28-3S%29%2F%28nh%29%29+%29%29%2F2+\"
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\n" ); document.write( "\"r+=+%28-12+%2B-+sqrt%28144%2B4%28%283S%29%2F%28nh%29%29+%29%29%2F2+\"
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