document.write( "Question 686131: two cars traveled in opposite directions from the same starting point. The rate of one car was 10km less than the rate of the other. After 4 hours the cars were 600km apart. Find the rate of each car \n" ); document.write( "

Algebra.Com's Answer #424707 by josmiceli(19441) $\"\"$ $\"About$

You can put this solution on YOUR website!
I think of one car as standing still and the other car
\n" ); document.write( "moving away from it at the sum of their speeds
\n" ); document.write( "Let $\"+s+\"$ = the speed of the faster car in km/hr
\n" ); document.write( " $\"+s+-+10+\"$ = the speed of the slower car in km/hr
\n" ); document.write( "---------------
\n" ); document.write( " $\"+600+=+%28+s+%2B+s+-+10+%29%2A4+\"$
\n" ); document.write( " $\"+600+=+%28+2s+-+10+%29%2A4+\"$
\n" ); document.write( " $\"+600+=+8s+-+40+\"$
\n" ); document.write( " $\"+8s+=+640+\"$
\n" ); document.write( " $\"+s+=+80+\"$
\n" ); document.write( " $\"+s+-+10+=+70+\"$
\n" ); document.write( "The speeds of the cars were 80 km/hr and 70 km/hr
\n" ); document.write( "check:
\n" ); document.write( " $\"+d%5B1%5D+=+80%2A4+\"$
\n" ); document.write( " $\"+d%5B1%5D+=+320+\"$
\n" ); document.write( "and
\n" ); document.write( " $\"+d%5B2%5D+=+70%2A4+\"$
\n" ); document.write( " $\"+d%5B2%5D+=+280+\"$
\n" ); document.write( "and
\n" ); document.write( " $\"+d%5B1%5D+%2B+d%5B2%5D+=+320+%2B+280+\"$
\n" ); document.write( " $\"+d%5B1%5D+%2B+d%5B2%5D+=+600+\"$
\n" ); document.write( "OK \n" ); document.write( "

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