document.write( "Question 1175958: In the diagram, AB || DG and AD || FG. If AB = 3, BC = 2, AC = 4, CE = 4, and EF = 5, what is the sum of the measures of the sides of the triangles? Express your answer as a common fraction. \r
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document.write( "My thoughts, the once that are parallel are equal to each other, so I think the total will be 1/6. \r
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document.write( "Please correct me\r
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document.write( "Link to the diagram - https://drive.google.com/file/d/1-Vuzfqi9S4GsXXKwbWqOJXlsCFfAuTMl/view?usp=sharing \n" );
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Algebra.Com's Answer #801769 by Theo(13342)![]() ![]() You can put this solution on YOUR website! here's the deal.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "AD is parallel to FG. \n" ); document.write( "this makes angle GFE equal to angle DCE because they are alternate interior angles to those two parallel lines. \n" ); document.write( "those angles are labeled as 2 in my diagram. \n" ); document.write( "also angle FGE is equal to angle EDC because they are alternate interior angles to the same two parallel lines. \n" ); document.write( "those angles are labeled as 1 in my diagram.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "AB is parallel to DG. \n" ); document.write( "this makes angles BAC equal to angle CDE because they are alternate interior angles to those two parallel lines. \n" ); document.write( "those angles are labeled 1 in my diagram. \n" ); document.write( "also angle CBA is equal to angle DEC because they are alternate interior angles to those two parallel lines. \n" ); document.write( "those angles are labeled 3 in my diagram.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "you also have angle BCA = angle DCE because they are vertical angles to each other. \n" ); document.write( "those two angles are labeled 2 in my diagram.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "you also have angle DEC equal to angle GEF because they are vertical angles to each other. \n" ); document.write( "those two angles are labeled 3 in my diagram.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "the bottom line is that triangles ABC and DEC and GEF are all similar to each other because their angles are equal. \n" ); document.write( "since they are similar to each other, their sides are proportional.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "the ratio from triangle DEC to ABC is 2/1. \n" ); document.write( "the ratio from triangle GEF to ABC is 5/2. \n" ); document.write( "the ratio from triangle GEF to DEC is 5/4.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "this means that corresponding sides of these triangle will have the same ratio to each other.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "to find the corresponding sides, you look for the sides opposite the angles that are equal to each other.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "example:\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "BC is opposite angle 1 in its triangle and CE is opposite angle 1 in its triangle. \n" ); document.write( "the ratio between those two triangle is 2/1, so if BC is 2 then CE is 4. \n" ); document.write( "this was one of the givens and was used to get the ratio for the other sides. \n" ); document.write( "since AB was 3 and is opposite angle 2 in its triangle, then DE is 6 because it is opposite angle 2 in its triangle.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "likewise angle 1 from triangle ABC is equal to angle 1 from triangle GEF. \n" ); document.write( "the side opposite angle 1 in triangle ABE is equal to 2 and the side opposite angle 1 in triangle GEF is equal to 5. \n" ); document.write( "this sets the ratio of the sides as 5/2 from triangle GEF to ABC.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "likewise the side opposite angle 1 in triangle DEC is equal to 4 and the side opposite angle 1 in triangle GEF is equal to 5. \n" ); document.write( "this sets the ratio of sides as 5/4 from triangle GEF to DEC.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "you use those ratios to get the rest of the corresponding sides of each triangle.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "now that you know what all the sides measure, you can get their sum.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "you can add each one up individually to get a sum of 49.5\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "or, .....\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "you can sum up the sides of triangle ABC to get 9. \n" ); document.write( "since the ratio of triangle DEC to ABC is 2 to 1, then the sum for triangle DEC is 2/1 * 9 = 18. \n" ); document.write( "since the ratio of triangle GEF to ABC is 5/2,then the sum for triangle GEF is 5/2 * 9 = 22.5 \n" ); document.write( "9 + 18 + 22.5 = 49.5. \n" ); document.write( "same answer.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "here's my diagram.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "note that the transversals to parallel lines AB and DG are AD and BE.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "note also that the transversals to parallel lines AD and GF are DG and CF.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "here's my diagram and yours below it.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " ![]() \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " ![]() |