document.write( "Question 969688: An isoceles triangle has congruent sides that each measure 3 feet and a base angle of measure of x as shown in the sketch. The third side has a whole number length, if x <60 degrees , what are the possibilities of the perimeter of the triangle? \n" ); document.write( "
Algebra.Com's Answer #592490 by josgarithmetic(39617)\"\" \"About 
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v, the vertex angle.
\n" ); document.write( "\"v%2Bx%2Bx=180\"
\n" ); document.write( "\"v=180-2x\"\r
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\n" ); document.write( "\n" ); document.write( "One objective is to find a formula for the base length.
\n" ); document.write( "b, the length of the base.
\n" ); document.write( "Law of Cosines:
\n" ); document.write( "\"3%5E2%2B3%5E3-2%2A3%2A3%2Acos%28v%29=b%5E2\"\r
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\n" ); document.write( "\n" ); document.write( "\"18-18%2Acos%28v%29=b%5E2\"
\n" ); document.write( "\"b%5E2=18-18%2Acos%28180-2x%29\"-----Think or inspect this angle on The Unit Circle.\r
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\n" ); document.write( "\n" ); document.write( ".... \"cos%28180-2x%29=-cos%282x%29\".\r
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\n" ); document.write( "\n" ); document.write( "Revise the equation for \"b%5E2\".
\n" ); document.write( "\"b%5E2=18%2B18%2Acos%282x%29\"\r
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\n" ); document.write( "\n" ); document.write( "The isosceles triangle to have any meaning and match the given requirement, \"0%3Cx%3C60\".\r
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\n" ); document.write( "\n" ); document.write( "Perimeter:
\n" ); document.write( "\"6%2Bsqrt%2818%2B18%2Acos%280%29%29%3Eperimeter%3E6%2Bsqrt%2818%2B18cos%28120%29%29\"
\n" ); document.write( "\"6%2Bsqrt%2818%2B18%2A1%29%3Eperimeter%3E6%2Bsqrt%2818%2B18%2A%28-cos%2860%29%29%29\", again refer to Unit Circle to see.
\n" ); document.write( "\"6%2Bsqrt%2836%29%3Eperimeter%3E6%2Bsqrt%2818%2B18%2A%281%2F2%29%29\"
\n" ); document.write( "\"12%3Eperimeter%3E6%2Bsqrt%2827%29\"
\n" ); document.write( "\"highlight%2812%3Eperimeter%3E6%2B3%2Asqrt%283%29%29\"
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