document.write( "Question 817109: it takes 5 hours for a boat to go a distance of 15 miles against the current and 3 hours in the direction of the current. what is the speed of the boat in stil water and what is the speed of the current
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Algebra.Com's Answer #491881 by mananth(16946)![]() ![]() You can put this solution on YOUR website! boat speed =x mph \n" ); document.write( "current speed =y mph \n" ); document.write( "against current 5 hours \n" ); document.write( "with current 3 hours \n" ); document.write( " \n" ); document.write( "Distance against 15 miles distance with 15 miles \n" ); document.write( "t=d/r against current - \n" ); document.write( "15.00 / ( x - y )= 5.00 \n" ); document.write( "5.00 ( x - y ) = 3.00 \n" ); document.write( "5.00 x - 5.00 y = 15.00 ....................1 \n" ); document.write( " \n" ); document.write( "15.00 / ( x + y )= 3.00 \n" ); document.write( "3.00 ( x + y ) = 15.00 \n" ); document.write( "3.00 x + 3.00 y = 15.00 ...............2 \n" ); document.write( "Multiply (1) by 3.00 \n" ); document.write( "Multiply (2) by 5.00 \n" ); document.write( "we get \n" ); document.write( "15.00 x + -15.00 y = 45.00 \n" ); document.write( "15.00 x + 15.00 y = 75.00 \n" ); document.write( "30.00 x = 120.00 \n" ); document.write( "/ 30.00 \n" ); document.write( "x = 4.00 mph \n" ); document.write( " \n" ); document.write( "plug value of x in (1) y \n" ); document.write( "5.00 x -5.00 y = 15.00 \n" ); document.write( "20.00 -5.00 -20.00 = 15.00 \n" ); document.write( "-5.00 y = 15.00 \n" ); document.write( "-5.00 y = -5.00 mph \n" ); document.write( " y = 1.00 \n" ); document.write( "boat speed 4.00 mph \n" ); document.write( "current speed 1.00 mph \n" ); document.write( " \n" ); document.write( "m.ananth@hotmail.ca \n" ); document.write( " \n" ); document.write( " |