document.write( "Question 17553: Steve traveled 600 miles at a certain speed. Had he gone 20mph faster, the trip would have taken one hour less. Find the speed of his vehicle. What would the equation look like for this word problem? \n" ); document.write( "

Algebra.Com's Answer #8497 by xcentaur(357) $\"\"$ $\"About$

You can put this solution on YOUR website!
Distance=600miles,Speed=x mph
\n" ); document.write( "Time taken=(600/x)hours
\n" ); document.write( "

\n" ); document.write( "Second case:
\n" ); document.write( "Distance=600miles,Speed=(x+20)mph
\n" ); document.write( "Time=(600/x+20)hours which we know is 1 hour less than the first case
\n" ); document.write( "

\n" ); document.write( "So we get,
\n" ); document.write( " $\"+%28600%2Fx%29+-+%28600%2F%28x%2B20%29%29+=+1+\"$
\n" ); document.write( "[This is your required equation]
\n" ); document.write( " $\"+%28600%28x%2B20%29-600x%29%2F%28x%28x%2B20%29%29+=+1+\"$ \r
\n" ); document.write( "\n" ); document.write( " $\"+%28600x%2B12000-600x%29%2F%28x%5E2%2B20x%29+=+1+\"$ \r
\n" ); document.write( "\n" ); document.write( " $\"+12000+=+x%5E2%2B20x+\"$ \r
\n" ); document.write( "\n" ); document.write( " $\"+x%5E2%2B20x-12000+=+0+\"$ \r
\n" ); document.write( "\n" ); document.write( "This is a quadratic in x and can thus be solved as:\r
\n" ); document.write( "\n" ); document.write( " $\"+x%5E2%2B20x-12000+=+0+\"$ \r
\n" ); document.write( "\n" ); document.write( " $\"+%28x-100%29%28x%2B120%29+=+0+\"$ \r
\n" ); document.write( "\n" ); document.write( "So we get x=100 or -120 mph\r
\n" ); document.write( "\n" ); document.write( "This speed cannot be negative, thus x=100
\n" ); document.write( "

\n" ); document.write( "Hope this helps,
\n" ); document.write( "prabhat \n" ); document.write( "

\n" );