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document.write( "(a) To find the area of the triangle, use the Heron's formula.\r\n" );
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document.write( " On the Heron's formula, see the lessons\r\n" );
document.write( " Proof of the Heron's formula for the area of a triangle \r\n" );
document.write( " One more proof of the Heron's formula for the area of a triangle \r\n" );
document.write( " in this site.\r\n" );
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document.write( " The semi-perimeter is equal to s =
= 20 cm.\r\n" );
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document.write( " The area of the triangle is (Heron's formula)\r\n" );
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document.write( " A =
=
=
=
= 56.57 cm^2 (approximately). ANSWER\r\n" );
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document.write( "(b) Altitude to the longest side.\r\n" );
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document.write( " Let h be the altitude to the longest side.\r\n" );
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document.write( " Then for the area of the triangle,\r\n" );
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document.write( " A =
= 56.57 cm^2,\r\n" );
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document.write( " which implies \r\n" );
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document.write( " h =
= 6.29 cm (approximately). ANSWER\r\n" );
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document.write( "(c) The median to the longest side.\r\n" );
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document.write( " In a triangle with the sides \"a\", \"b\" and \"c\", the median drawn to the side \"c\" has the length of \r\n" );
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=
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document.write( " For this theorem, see the lesson\r\n" );
document.write( " The length of a median of a triangle\r\n" );
document.write( " in this site.\r\n" );
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document.write( " Substitute the given data a= 12, b= 10, c= 18 to get the length of the median drawn to the side of the length 18 cm\r\n" );
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= 6.403 cm. ANSWER\r\n" );
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document.write( "d. The length of angle bisector of the largest angle of the triangle.\r\n" );
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document.write( " If the triangle is not isosceles, then this problem (this question) is FAR BEYOND any school Math curriculum.\r\n" );
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document.write( "e. The line segment joining the midpoints of 12 cm and 18 cm sides\r\n" );
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document.write( " It is called \"the mid-segment\" of the triangle.\r\n" );
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document.write( " It is widely known that the mid-segment length is half of the length of the parallel side of the triangle.\r\n" );
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document.write( " So, the answer is
= 5 cm in this case.\r\n" );
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document.write( "My advise to you for the future:\r
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document.write( " Do not include so many questions in your posts.\r\n" );
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