document.write( "Question 1074278: In triangle RST, U lies on TS with TU:US= 2:3. M is the midpoint of RU. TM intersects RS in V. Find the ratio of RV:RS.
\n" ); document.write( "I was able to solve it with trig, and I got 2:7. It was meant to be solved with basic geometry, but I haven't be able to think of a way.
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Algebra.Com's Answer #689017 by KMST(5328)\"\" \"About 
You can put this solution on YOUR website!
Maybe by now you have been able to think of a way.
\n" ); document.write( "I could not think of a way late last night,
\n" ); document.write( "but I woke up with a clearer mind this morning,
\n" ); document.write( "so I added line MW, parallel to ST:
\n" ); document.write( " MW is part of two new triangles similar to two triangles that were there before.
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\n" ); document.write( "Now that I look at the drawing,
\n" ); document.write( "I realize it has TU:RS = 3:2 .
\n" ); document.write( "A drawing is not necessary to support the reasoning,
\n" ); document.write( "but even an inaccurate drawing helps
\n" ); document.write( "as a reminder of the meaning of each point.
\n" ); document.write( "
\n" ); document.write( "RWM is similar to RSU.
\n" ); document.write( "MVW is similar to TVS.
\n" ); document.write( "The \"scale down factors\" between the similar triangles
\n" ); document.write( "lead to a way to calculate the lengths of RW and VW
\n" ); document.write( "as fractions of the length pf RS,
\n" ); document.write( "and that allows to calculate, as a fraction of the length of RS,
\n" ); document.write( "the lengths of \"RV=RW-VW\" .
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\n" ); document.write( "Since \"TU%2BUS=TS\" and \"TU%3AUS+=+2%3A3\" ,
\n" ); document.write( "\"TU%3AUS%3ATS+=+2%3A3%3A3%2B2=5\"
\n" ); document.write( "So,
\n" ); document.write( "\"TU=%282%2F5%29TS\" and \"US=%283%2F5%29TS\" .
\n" ); document.write( "Since M is the midpoint of RU,
\n" ); document.write( "and WM is parallel to ST,
\n" ); document.write( "RWM is not only similar to RSU;
\n" ); document.write( "it is a \"1%2F2\" scale version of RSU.
\n" ); document.write( "So, not only is MW the midsegment of RSU,
\n" ); document.write( "with \"MW=%281%2F2%29US\" ,
\n" ); document.write( "but also \"RW=%281%2F2%29RS\" ,
\n" ); document.write( "and of course, \"WS=%281%2F2%29RS\" too.
\n" ); document.write( "
\n" ); document.write( "\"MW=%281%2F2%29US=%281%2F2%29%283%2F5%29TS=%283%2F10%29TS\" .
\n" ); document.write( "Since MVW is similar to TVS,
\n" ); document.write( "and \"MW=%283%2F10%29TS\" , \"VW=%283%2F10%29VS\" .
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\n" ); document.write( "Finally,
\n" ); document.write( "\"system%28VS=VW%2BWS=VW%2B%281%2F2%29RS%2CVW=%283%2F10%29VS%29\" --> \"VS=%283%2F10%29VS%2B%281%2F2%29RS\" .
\n" ); document.write( "Form there,
\n" ); document.write( "\"VS-%283%2F10%29VS=%281%2F2%29RS\" --> \"%287%2F10%29VS=%281%2F2%29RS\" --> \"VS=%2810%2F7%29%281%2F2%29RS\" --> \"VS=%285%2F7%29RS\" ,
\n" ); document.write( "and \"RV=RS-VS\" --> \"RV=RS-%285%2F7%29RS\" --> \"highlight%28RV=%282%2F7%29RS%29\"
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\n" ); document.write( "NOTE:
\n" ); document.write( "I am not sure if the reasoning above is the shortest way to the answer.
\n" ); document.write( "Maybe I should have drawn a line through M parallel to RS instead.
\n" ); document.write( "With nothing else to do, I would explore other angles to this problem
\n" ); document.write( "(and draw a better drawing).
\n" ); document.write( "However, if you are still looking for a geometry-based answer,
\n" ); document.write( "a less than perfect answer is better than no answer.
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