document.write( "Question 894333: A rectangle ABCD, which is 40 inches high by 20 wide, leans so that its top is 4 inches to the right of vertical.
\n" ); document.write( "ie corner A (top left) is 4 inches to the right of corner D (bottom left).\r
\n" ); document.write( "\n" ); document.write( "By how much must I lift corner C to make the sides AD and BC vertical?
\n" ); document.write( "(and how do you work it out accurately?)
\n" ); document.write( "The answer will be about 2 inches but that's logic, not maths.\r
\n" ); document.write( "\n" ); document.write( "Thank you for your help.
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Algebra.Com's Answer #541968 by Theo(13342)\"\" \"About 
You can put this solution on YOUR website!
your logic is correct.
\n" ); document.write( "the solution is 2.\r
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\n" ); document.write( "\n" ); document.write( "i solved it using trigonometry, but it was quite messy and required the use of the calculator. the solution, however, turned out to be exactly 2.\r
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\n" ); document.write( "\n" ); document.write( "i then looked at it geometrically and, while not obvious, it turns out that the triangles are similar and, since similar triangles have proportional sides, you get a ratio of x/20 = 4/40 and you wind up with x = 2, x being the height you are looking for. in the diagram shown below, x represents the length of DB.\r
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\n" ); document.write( "\n" ); document.write( "the geometric logic has to do with parallel lines and vertical angles and complementary angles.\r
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\n" ); document.write( "\n" ); document.write( "it's a bit of a mish mash of geometric relationships.\r
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\n" ); document.write( "\n" ); document.write( "the following diagram with all the angles that are equal to each other that matter to the solution is shown below.\r
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\n" ); document.write( "\n" ); document.write( "look below the diagram for further comments.\r
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\n" ); document.write( "\n" ); document.write( "the bottom line on the geometric analysis is that triangle AFD is similar to triangle DGC because all their angles are equal.\r
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\n" ); document.write( "\n" ); document.write( "since the triangles are similar, their corresponding sides are proportional.\r
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\n" ); document.write( "\n" ); document.write( "FA is the side opposite angle FDA
\n" ); document.write( "DG is the side opposite angle GCD\r
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\n" ); document.write( "\n" ); document.write( "AD is the side opposite angle AFD
\n" ); document.write( "DC is the side opposite angle DGC\r
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\n" ); document.write( "\n" ); document.write( "their corresponding sides are proportional.\r
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\n" ); document.write( "\n" ); document.write( "you get 4/40 = DG / 20\r
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\n" ); document.write( "\n" ); document.write( "solve for DG and you get DG = 20*4/40 = 80/40 = 2\r
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\n" ); document.write( "\n" ); document.write( "that's your solution.\r
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\n" ); document.write( "\n" ); document.write( "point C has to be raised up to the height of point D in order for the rectangle to be vertically aligned.\r
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\n" ); document.write( "\n" ); document.write( "the height of point D from point G is equal to the length of DG which is equal to 2.\r
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\n" ); document.write( "\n" ); document.write( "i didn't show you the trigonometric solution because it appears you are in a geometry course rather than a trigonometry course.\r
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\n" ); document.write( "\n" ); document.write( "the trigonometry solution does confirm the geometric solution however, so no problem there.\r
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