document.write( "Question 444681: In one hour, Steve drives 25 miles farther in his car than John can cycle on his bike. If it takes John an hour and a half hours longer to cycle seventy five miles than it takes Steve in his car, how fast can John cycle? \n" ); document.write( "
Algebra.Com's Answer #306727 by ankor@dixie-net.com(22740)![]() ![]() You can put this solution on YOUR website! In one hour, Steve drives 25 miles farther in his car than John can cycle on his bike. \n" ); document.write( "If it takes John an hour and a half hours longer to cycle seventy five miles than it takes Steve in his car, how fast can John cycle? \n" ); document.write( ": \n" ); document.write( "Let c = speed that John can cycle \n" ); document.write( "Let d = speed Steve can drive \n" ); document.write( ": \n" ); document.write( "Write a distance equation for the statement: \n" ); document.write( "\"In one hour, Steve drives 25 miles farther in his car than John can cycle on his bike. \" \n" ); document.write( "Steve's dist - John's dist = 25 \n" ); document.write( "1d - 1c = 25 \n" ); document.write( "d = (c + 25) \n" ); document.write( ": \n" ); document.write( "Write a time equation for the statement, (time = dist/speed): \n" ); document.write( "\"If it takes John an hour and a half hours longer to cycle seventy five miles than it takes Steve in his car,\" \n" ); document.write( "John's travel time - Steve's travel time = 1.5 hrs \n" ); document.write( " \n" ); document.write( ": \n" ); document.write( "Replace s with (c+25) \n" ); document.write( " \n" ); document.write( ": \n" ); document.write( "Multiply by c(c+25), results \n" ); document.write( "75(c+25) - 75c = 1.5c(c+25) \n" ); document.write( "75c + 1875 - 75c = 1.5c^2 + 37.5c \n" ); document.write( ": \n" ); document.write( "Arrange as a quadratic equation \n" ); document.write( "1.5c^2 + 37.5c - 1875 = 0 \n" ); document.write( "; \n" ); document.write( "Get rid of those decimals, multiply by 2 \n" ); document.write( "3c^2 + 75c - 3750 = 0 \n" ); document.write( ": \n" ); document.write( "You can solve this using the quadratic formula, but this will factor to \n" ); document.write( "(3c + 150)(c - 25) = 0 \n" ); document.write( ": \n" ); document.write( "The positive solution \n" ); document.write( "c = 25 mph is the cycling speed \n" ); document.write( ": \n" ); document.write( ": \n" ); document.write( "To check this; find the driving speed \n" ); document.write( "d = c+25 \n" ); document.write( "d = 50 mph \n" ); document.write( "Find the time of each \n" ); document.write( "75/25 = 3 hrs \n" ); document.write( "75/50 = 1.5 \n" ); document.write( "--------------- \n" ); document.write( "differ: 1.5 hrs\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " |