document.write( "Question 1072946: A triangle has two equal sides and. Third side. Determine the ratio between the sides a and b to enclose the maximum area for a given total length of the sides? \n" ); document.write( "
Algebra.Com's Answer #687803 by Fombitz(32388)\"\" \"About 
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Look at an isosceles triangle with sides, m, m, and 2n.
\n" ); document.write( "So that
\n" ); document.write( "\"m=a\"
\n" ); document.write( "\"n=b%2F2\"
\n" ); document.write( "The perimeter is then,
\n" ); document.write( "\"P=m%2Bm%2B2n\"
\n" ); document.write( "\"P=2m%2B2n\"
\n" ); document.write( "The perimeter is set to a constant length, 2L.
\n" ); document.write( "\"2m%2B2n=2L\"
\n" ); document.write( "\"m%2Bn=L\"
\n" ); document.write( "\"n=L-m\"
\n" ); document.write( "The area would then be,
\n" ); document.write( "\"A=%281%2F2%29%28Base%29%28Height%29\"
\n" ); document.write( "\"A=%281%2F2%29n%28sqrt%28m%5E2-n%5E2%29%29\"
\n" ); document.write( "Substituting for n,
\n" ); document.write( "\"A=%281%2F2%29%28L-m%29%28sqrt%28m%5E2-%28L-m%29%5E2%29%29\"
\n" ); document.write( "\"A=%281%2F2%29%28L-m%29%28sqrt%282mL-L%5E2%29%29\"
\n" ); document.write( "So to find the maximum area, take the derivative of A with respect to a and set it equal to zero.
\n" ); document.write( "\"dA%2Fda=%28L%282L-3m%29%29%2F%282%28sqrt%282mL-L%5E2%29%29%29\"
\n" ); document.write( "\"%28L%282L-3m%29%29=0\"
\n" ); document.write( "One solution,
\n" ); document.write( "\"2L-3m=0\"
\n" ); document.write( "\"3m=2L\"
\n" ); document.write( "\"m=%282%2F3%29L\"
\n" ); document.write( "and
\n" ); document.write( "\"n=L-%282%2F3%29L\"
\n" ); document.write( "\"n=%281%2F3%29L\"
\n" ); document.write( "So in terms of a and b,
\n" ); document.write( "\"m=a\"
\n" ); document.write( "and
\n" ); document.write( "\"n=b%2F2\"
\n" ); document.write( "So substituting,
\n" ); document.write( "\"a=%282%2F3%29L\"
\n" ); document.write( "and
\n" ); document.write( "\"b%2F2=%281%2F3%29L\"
\n" ); document.write( "\"b=%282%2F3%29L\"
\n" ); document.write( "So the ratio is,
\n" ); document.write( "\"a%2Fb=%28%282%2F3%29L%29%2F%28%282%2F3%29L%29\"
\n" ); document.write( "\"highlight%28a%2Fb=1%29\"
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