document.write( "Question 692844: A pleasant day Sir/ Madam, my daughter has this problem in geometry and I am not good in geometric proofs, can you please help me?\r
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document.write( "the illustration or drawing is a rectangle inscribed in a circle
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document.write( "Given: Quadrilateral ABCD is a rectangle
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document.write( "Prove: line segment AC and line segment BD are diameters of the circle\r
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document.write( "Thank you very much for anyone who can help me! \n" );
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Algebra.Com's Answer #427124 by MathLover1(20850)![]() ![]() You can put this solution on YOUR website! \n" ); document.write( "first draw the picture:\r \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "next, we will need to prove this: \n" ); document.write( "theorem: Diagonal of any rectangle inscribed in a circle is a diameter of the circle. (\r \n" ); document.write( "\n" ); document.write( "This is essentially the converse of Thales' theorem.\r \n" ); document.write( "\n" ); document.write( "Let A, B, C and D be the vertices of a rectangle inscribed in a circle and let AC and BD be the diagonals of this rectangle. \r \n" ); document.write( "\n" ); document.write( "We can now focus on any one of the four triangles: \r \n" ); document.write( "\n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Let's take \n" ); document.write( "\n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( "The angle at \n" ); document.write( "\n" ); document.write( "Hence, looking at the triangle \n" ); document.write( "\n" ); document.write( "Therefore to prove (1), we need to show that side \n" ); document.write( "\n" ); document.write( "Proof: \r \n" ); document.write( "\n" ); document.write( "Choose any three points \n" ); document.write( "\n" ); document.write( "Let's suppose that the claim is that the angle at \n" ); document.write( "\n" ); document.write( "We will show that if this is true then it must follow that \n" ); document.write( "Connect the center of the circle ( \n" ); document.write( "\n" ); document.write( "Let's call the angle defined by the path \n" ); document.write( "\n" ); document.write( "Since \n" ); document.write( "\n" ); document.write( "We will next want to find the angle between \n" ); document.write( "The angle between \n" ); document.write( "\n" ); document.write( "Similarly, the angle between \n" ); document.write( "\n" ); document.write( "Finally, since all the three angles at \n" ); document.write( "\n" ); document.write( "However, the angle at \n" ); document.write( "\n" ); document.write( "This angle was claimed to be \n" ); document.write( "\n" ); document.write( "This means that the points \n" ); document.write( "\n" ); document.write( "In other words, the \n" ); document.write( "\n" ); document.write( "So, we can conclude that \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " |