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document.write( "I have another solution and another answer.\r
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document.write( "The side length of the larger square is (6+12) = 18 centimeters, so its area is
= 324 cm^2.\r\n" );
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document.write( "Now, there are 4 congruent right angled triangles ALD, DKC, CBJ and BIA.\r\n" );
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document.write( "The area of the smaller square is 324 cm^2 MINUS 4 times the area of the triangle ALD.\r\n" );
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document.write( "Triangle ALD is similar to triangle ADH (they both are right angled triangles and have common acute angle DAL).\r\n" );
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document.write( "Triangle ALD has the hypotenuse AD = 6+12 = 18 cm.\r\n" );
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document.write( "Triangle ADH has the hypotenuse AH =
=
=
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document.write( "The ratio of the hypotenuses |AH|/|AD| =
=
(the similarity coefficient).\r\n" );
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document.write( "Hence, the ratio of the areas of the triangles ADH and ALD is the square of the similarity coefficient, i.e.
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document.write( "The area of the triangle ADH is
= 54 cm^2.\r\n" );
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document.write( "Hence, the area of the triangle ALD is
cm^2 = 48.6 cm^2.\r\n" );
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document.write( "Then the area of the smaller square is (as I explained it above) 324 - 4*48.6 = 129.6 cm^2. ANSWER\r\n" );
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