document.write( "Question 106158: another problem..\r
\n" ); document.write( "\n" ); document.write( "If a bus traveled 10 km/h faster, it would take 2h less time to make a 315km trip. What is its speed?\r
\n" ); document.write( "\n" ); document.write( "Thanks!
\n" ); document.write( "

Algebra.Com's Answer #77278 by HyperBrain(694)\"\" \"About 
You can put this solution on YOUR website!
Let x=the original speed
\n" ); document.write( "____x+10=the increased speed\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\"speed=distance%2Ftime\"
\n" ); document.write( "\"time=distance%2Fspeed\"\r
\n" ); document.write( "\n" ); document.write( "If a bus traveled 10 km/h faster, it would take 2h less time to make a 315km trip\r
\n" ); document.write( "\n" ); document.write( "time for the car traveling with its orig. speed=\"315%2Fx\"\r
\n" ); document.write( "\n" ); document.write( "time for the car with faster speed =\"%28315%2F%28x%2B10%29%29-2\"\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "This means that:\r
\n" ); document.write( "\n" ); document.write( "\"%28315%2Fx%29%2B2=315%2F%28x%2B10%29\"
\n" ); document.write( "\"%28x%28x%2B10%29%29%28%28315%2Fx%29%2B2%29=%28x%28x%2B10%29%29%28315%2F%28x%2B10%29%29\"
\n" ); document.write( "\"315%28x%2B10%29%2B2x%28x%2B10%29=315x\"
\n" ); document.write( "\"315x%2B3150%2B2x%5E2%2B20x=315x\"
\n" ); document.write( "\"2x%5E2%2B315x%2B20x%2B3150=315x\"
\n" ); document.write( "\"2x%5E2%2B335x%2B3150=315x\"
\n" ); document.write( "\"2x%5E2%2B335x-315x%2B3150=315x-315x\"
\n" ); document.write( "\"2x%5E2%2B20x%2B3150=0\"
\n" ); document.write( "\"x%5E2%2B10x%2B1575=0\"\r
\n" ); document.write( "\n" ); document.write( "Using the quadratic formula,\r
\n" ); document.write( "\n" ); document.write( "\"x=%28-10%2B-sqrt%2810%5E2-4%2A1%2A1575%29%29%2F%282%2A1%29\"\r
\n" ); document.write( "\n" ); document.write( "The discriminant is negative------the roots are unequal and imaginary(see my lesson,\"Don't discriminate the DISCRIMINANT!!!!!\" and,\r
\n" ); document.write( "\n" ); document.write( "therefore, there is no solution!\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "Power up,
\n" ); document.write( "HyperBrain!
\n" ); document.write( "
\n" );