document.write( "Question 557423: The first two sections of a bicycle race are x and y meters long. Annie cycles the first part of the race at 6m/s and the second part at 12m/s. Barry cycles the same sections at 10m/s and 6m/s. It takes Annie half a minute to cycle these two sections, whereas it takes Barry 46 seconds to cover the same distance. \r
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document.write( "How long are these two sections of the race? \n" );
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Algebra.Com's Answer #362860 by ankor@dixie-net.com(22740)![]() ![]() You can put this solution on YOUR website! The first two sections of a bicycle race are x and y meters long. \n" ); document.write( " Annie cycles the first part of the race at 6m/s and the second part at 12m/s \n" ); document.write( " Barry cycles the same sections at 10m/s and 6m/s. It takes Annie half a minute to cycle these two sections, whereas it takes Barry 46 seconds to cover the same distance. \n" ); document.write( "How long are these two sections of the race? \n" ); document.write( ": \n" ); document.write( "Write a time equation for each; time = dist/speed. simplify each equation \n" ); document.write( ": \n" ); document.write( "First cyclist: \n" ); document.write( " \n" ); document.write( "Multiply by 12, to clear the denominators, results \n" ); document.write( "2x + y = 360 \n" ); document.write( ": \n" ); document.write( "2nd cyclist: \n" ); document.write( "multiply by 30 \n" ); document.write( "3x + 5y = 1380 \n" ); document.write( "Multiply the 1st equation by 5, subtract the above equation \n" ); document.write( "10x + 5y = 1800 \n" ); document.write( "3x + 5y = 1380 \n" ); document.write( "----------------subtraction eliminates y, find x \n" ); document.write( "7x = 420 \n" ); document.write( "x = 420/7 \n" ); document.write( "x = 60 meters is the 1st part \n" ); document.write( "and \n" ); document.write( "y = -2x + 360 \n" ); document.write( "y = -2(60) + 360 \n" ); document.write( "y = 240 meters is the 2nd part \n" ); document.write( ": \n" ); document.write( ": \n" ); document.write( "Check this; find the time of the 1st cyclist \n" ); document.write( "60/6 + 240/12 \n" ); document.write( "10 + 20 = 30 sec \n" ); document.write( "and the 2nd cyclist time \n" ); document.write( "60/10 + 240/6 = \n" ); document.write( "6 + 40 = 46 sec \n" ); document.write( " \n" ); document.write( " |