document.write( "Question 662142: A man is travelling at speed x to town, 240km from home, he calculates that if his speed is increased by 10km/h then he will take 48 minutes less time to complete the journey. what will be his original speed?
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Algebra.Com's Answer #411979 by ewatrrr(24785) $\"\"$ $\"About$

You can put this solution on YOUR website!

 
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document.write( "Hi,
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document.write( "speed x to town, 240km from home 
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document.write( "if his speed is increased by 10km/h then he will take 48 minutes(.8hr) less
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document.write( " t = D/r
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document.write( "  |Multiplying thru by 10x(x+10) so as all denominators = 1
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document.write( " 2400(x+10) - 8x(x+10) = 2400x
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document.write( " 2400x + 24000 - 8x^2 - 80x = 2400x
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document.write( "    -8x^2 - 80x + 24000 = 0
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document.write( "     x^2 + 10x - 3000 = 0
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document.write( "factoring
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document.write( "   (x + 60)(x-50)= 0,   x = 50mph   (throwing out negative solution for unit measure)
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document.write( "and ...
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