document.write( "Question 96972: A bike race consists of two segments whose total length is 90 km. The first segment is covered at 10 kph and takes 2 hours longer to complete than the second segment, which is covered at 25 kph. How long is each segment?\r
\n" ); document.write( "\n" ); document.write( "I have tried setting it up as t/25 = (t+2)/10 but for some reason I can't figure out the algebra.\r
\n" ); document.write( "\n" ); document.write( "Thanks!
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Algebra.Com's Answer #70600 by Earlsdon(6294)\"\" \"About 
You can put this solution on YOUR website!
From your equation, it appears that you assumed that the two segments were the same distance, but there is nothing in the problem to support this assumption.
\n" ); document.write( "So, back to basics:
\n" ); document.write( "\"d%5B1%5D+=+r%5B1%5Dt%5B1%5D\" and...
\n" ); document.write( "\"d%5B2%5D+=+r%5B2%5Dt%5B2%5D\"
\n" ); document.write( "We know that:
\n" ); document.write( "\"r%5B1%5D+=+10\" and...
\n" ); document.write( "\"r%5B2%5D+=+25\"
\n" ); document.write( "\"t%5B1%5D+=+t%5B2%5D+%2B+2\" and we also know that:
\n" ); document.write( "\"d%5B1%5D%2Bd%5B2%5D+=+90\" So we can write:
\n" ); document.write( "\"d%5B1%5D+=+10t%5B1%5D\"
\n" ); document.write( "\"d%5B2%5D+=+25t%5B2%5D\" aagh...to many variables! Let's replace \"t%5B1%5D\" with \"t%5B2%5D%2B2\" and replace \"d%5B2%5D\" with \"90-d%5B1%5D\", so now we have:
\n" ); document.write( "\"d%5B1%5D+=+10%28t%5B2%5D%2B2%29\" and
\n" ); document.write( "\"90-d%5B1%5D+=+25t%5B2%5D\" Solve this for \"d%5B1%5D\"
\n" ); document.write( "\"d%5B1%5D+=+90-25t%5B2%5D\"...but, of course, \"d%5B1%5D+=+d%5B1%5D\", so...
\n" ); document.write( "\"10%28t%5B2%5D%2B2%29+=+90-25t%5B2%5D\" Good, now we have one variable \"t%5B2%5D\", so let's solve for it.
\n" ); document.write( "\"10t%5B2%5D%2B20+=+90-25t%5B2%5D\"
\n" ); document.write( "\"35t%5B2%5D%2B20+=+90\"
\n" ); document.write( "\"35t%5B2%5D+=+70\" and...
\n" ); document.write( "\"t%5B2%5D+=+2\"hrs. Now we can find \"d%5B1%5D\" and \"d%5B2%5D\"
\n" ); document.write( "\"d%5B1%5D+=+10%28t%5B2%5D%2B2%29\"
\n" ); document.write( "\"d%5B1%5D+=+10%282%2B2%29\"
\n" ); document.write( "\"d%5B1%5D+=+40\"km and...
\n" ); document.write( "\"d%5B2%5D+=+90-d%5B1%5D\"
\n" ); document.write( "\"d%5B2%5D+=+90-40\"
\n" ); document.write( "\"d%5B2%5D+=+50\"km\r
\n" ); document.write( "\n" ); document.write( "Check:
\n" ); document.write( "Total distance is \"d%5B1%5D%2Bd%5B2%5D+=+40%2B50\" = 90km
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