document.write( "Question 1150800: Land in the shape of an isosceles triangle has a base of 130 m. An altitude from
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Algebra.Com's Answer #772272 by ikleyn(52832) $\"\"$ $\"About$

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document.write( "Red line  CE  is the altitude in triangle ABC drawn to the base.\r\n" );
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document.write( "Green line BD is the altitude drawn from the base vertex B to the lateral side AC.\r\n" );
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document.write( "Triangle ABD is a right angled triangle with the hypotenuse of 130 meters and the leg BD of 120 meters.\r\n" );
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document.write( "Hence, it is (5,12,13)-triangle and its leg AD is 50 meters.\r\n" );
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document.write( "Thus the area of the triangle ABD is   = 3000 square meters.\r\n" );
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document.write( "Triangle ACE is similar to the triangle ABD (since they both are right angled triangles and have common acute angle A).\r\n" );
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document.write( "The similarity coefficient is the ratio of their shorter legs   = .\r\n" );
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document.write( "Therefore, the area of the triangle ACE is   = 30*169 square meters,\r\n" );
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document.write( "and the area of the triangle ABC is twice this value, i.e.  2*30*169 = 10140 square meters.    ANSWER\r\n" );
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