document.write( "Question 830129: Two trains depart a train station traveling in opposite directions. the one traveling north was going twice as fast as the one going south. after 4 hours they were 600 miles apart. how fast was the faster train going \n" ); document.write( "
Algebra.Com's Answer #500352 by TimothyLamb(4379)\"\" \"About 
You can put this solution on YOUR website!
---
\n" ); document.write( "x = fast train
\n" ); document.write( "y = slow train
\n" ); document.write( "x = 2y
\n" ); document.write( "---
\n" ); document.write( "relative speed of trains:
\n" ); document.write( "s = x + y
\n" ); document.write( "s = d/t
\n" ); document.write( "s = 600/4
\n" ); document.write( "s = 150 mph
\n" ); document.write( "x + y = 150
\n" ); document.write( "---
\n" ); document.write( "linear system:
\n" ); document.write( "x = 2y
\n" ); document.write( "x + y = 150
\n" ); document.write( "---
\n" ); document.write( "put the system of linear equations into standard form:
\n" ); document.write( "---
\n" ); document.write( "x - 2y = 0
\n" ); document.write( "x + y = 150
\n" ); document.write( "---
\n" ); document.write( "copy and paste the above linear system in standard form into this matrix-method solver:
\n" ); document.write( "https://sooeet.com/math/system-of-linear-equations-solver.php
\n" ); document.write( "---
\n" ); document.write( "solution:
\n" ); document.write( "x = fast train = 100 mph
\n" ); document.write( "y = slow train = 50 mph
\n" ); document.write( "---
\n" ); document.write( "Solve and graph linear equations:
\n" ); document.write( "https://sooeet.com/math/linear-equation-solver.php
\n" ); document.write( "---
\n" ); document.write( "Solve quadratic equations, quadratic formula:
\n" ); document.write( "https://sooeet.com/math/quadratic-formula-solver.php
\n" ); document.write( "---
\n" ); document.write( "Solve systems of linear equations up to 6-equations 6-variables:
\n" ); document.write( "https://sooeet.com/math/system-of-linear-equations-solver.php \n" ); document.write( "
\n" );