document.write( "Question 516178: Two riders depart from city a to city b. One rider rides at 12 mph and other rider at 18 mph. Slower rider takes 1.5 hours longer to ride the distance.
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document.write( "How long did it take both riders to reach the destination
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document.write( "How far is city a to city b?\r
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document.write( "HELP!!!! How am I supposed to figure out how far the cities are from each other without any information on one or the other? And 1.5 hours to ride the distance??? AARRRGGGHHHH!!!! \n" );
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Algebra.Com's Answer #344279 by gc2000(22)![]() ![]() You can put this solution on YOUR website! x = time for rider 1 to city b \n" ); document.write( "y = time for rider 2 to city b \n" ); document.write( "d = distance from a to city b \n" ); document.write( "d = (rate)*(time) \n" ); document.write( " \n" ); document.write( "what is known? two things: \n" ); document.write( "1. distance is same for both riders \n" ); document.write( "2. time for rider 2 is 1.5hrs longer, therefore the equation for this is: \n" ); document.write( "y = x + 1.5 \n" ); document.write( " \n" ); document.write( "therefore since distance is same: \n" ); document.write( "(rate rider1)*(time rider1) = (rate rider2)*(time rider2) \n" ); document.write( "(18mph)*(x hours) = (12mph)*(y hours) \n" ); document.write( " \n" ); document.write( "and substitute for y since y = x + 1.5: \n" ); document.write( "(18mph)*(x hours) = (12mph)*(x + 1.5 hours) \n" ); document.write( "18x = 12(x + 1.5) \n" ); document.write( "18x = 12x + 18 \n" ); document.write( "subtract 12x from both sides \n" ); document.write( "6x = 18 \n" ); document.write( "divide both sides by 6 \n" ); document.write( "x = 3 \n" ); document.write( " \n" ); document.write( "time for rider1 is 3hrs. \n" ); document.write( "time for rider2 is 3 + 1.5 = 4.5 hours \n" ); document.write( " \n" ); document.write( "how far? \n" ); document.write( "d = (r)(t) \n" ); document.write( "d = (18)(3) = 54 \n" ); document.write( "distance = 54 miles \n" ); document.write( " \n" ); document.write( "check by d = (r)(t) for rider 2: \n" ); document.write( "d = (12)(4.5) \n" ); document.write( "d = 54, yes--answer checks out\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " |