document.write( "Question 1170046: a tour bus leaves sacremento every friday evening at 5:00 pm for a 270 mile trip to las vegas. this week, however, the bus leaves at 5:30 pm. to arrive in las vegas on time, the driver drives 6 mph faster than usual. what is the buses usual speed ? \n" ); document.write( "

Algebra.Com's Answer #794917 by ikleyn(52781) $\"\"$ $\"About$

You can put this solution on YOUR website!
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document.write( "Let x be that unknown regular speed under the question.\r\n" );
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document.write( "Then you have this \"time\" equation\r\n" );
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document.write( "     -  = 0.5  of an hour  (or 30 minutes).     (1)\r\n" );
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document.write( "You may multiply both sides by x*(x+6); reduce to the standard form quadratic equation and then solve it to find x.\r\n" );
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document.write( "I will solve this equation MENTALLY.\r\n" );
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document.write( "For it, I will multiply both sides by 2. I will get then\r\n" );
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document.write( "     -  = 1,\r\n" );
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document.write( "and then the solution  x= 54 becomes OBVIOUS.\r\n" );
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document.write( "ANSWER.  The regular speed is 54 miles per hour.\r\n" );
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document.write( "CHECK.  Then equation (1)  takes the form   -  =  5 - 4.5 = 0.5  hour, confirming the answer.\r\n" );
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