document.write( "Question 867251: Two trains made the same 315-mile run. Since one train traveled 10 mph faster than the other, it arrived 2 hours earlier. Find the speed of each train. \n" ); document.write( "

Algebra.Com's Answer #522989 by lwsshak3(11628) $\"\"$ $\"About$

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Two trains made the same 315-mile run. Since one train traveled 10 mph faster than the other, it arrived 2 hours earlier. Find the speed of each train.
\n" ); document.write( "***
\n" ); document.write( "let x=speed of slower train
\n" ); document.write( "x+10=speed of faster train
\n" ); document.write( "travel time=distance/speed
\n" ); document.write( "...
\n" ); document.write( " $\"315%2Fx-315%2F%28x%2B10%29=2\"$
\n" ); document.write( "LCD:x(x+10)
\n" ); document.write( "315(x+10)-315x=2x(x+10)
\n" ); document.write( "315x+3150-315x=2x^2+20x
\n" ); document.write( "2x^2+20x-3150=0
\n" ); document.write( "x^2+10x-1575=0
\n" ); document.write( "(x+45)(x-35)=0
\n" ); document.write( "x=-45 (reject, x>0)
\n" ); document.write( "or
\n" ); document.write( "x=35
\n" ); document.write( "x+10=45
\n" ); document.write( "speed of slower train=35 mph
\n" ); document.write( "speed of faster train=45 mph \n" ); document.write( "

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