document.write( "Question 1167532: Anna drives 45 km to work. If she increases her usual average speed by 5 km/h, the time it takes her to drive to to work is decreased by 6 minutes. Find her usual speed \n" ); document.write( "

Algebra.Com's Answer #792141 by ikleyn(52777) $\"\"$ $\"About$

You can put this solution on YOUR website!
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document.write( "Use and solve this \"time\" equation\r\n" );
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document.write( "     -  =   of an hour  (= 6 minutes).\r\n" );
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document.write( "It is equivalent to\r\n" );
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document.write( "     -  = 1     (1)\r\n" );
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document.write( "and has an obvious solution  x = 45.\r\n" );
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document.write( "CHECK.    -  =  -  = 10 - 9 = 1.    ! Correct !\r\n" );
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document.write( "Alternatively, you can reduce the equation (1) to quadratic equation and solve it formally.\r\n" );
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\n" ); document.write( "\n" ); document.write( "Solved.\r
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