document.write( "Question 1139969: Mary makes monthly visits to her parents in Malacca, a distance of 240 km from Singapore.She finds that if she increases the speed by 10 km/hr , she could save a total of 20 minutes.
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Algebra.Com's Answer #760472 by MathTherapy(10552)\"\" \"About 
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\n" ); document.write( "Mary makes monthly visits to her parents in Malacca, a distance of 240 km from Singapore.She finds that if she increases the speed by 10 km/hr , she could save a total of 20 minutes.
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Actual time taken, with S being the speed: \"240%2FS\"
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document.write( "Hypothetical time, with S + 10 being the hypothetical speed: \"240%2F%28S+%2B+10%29\"
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document.write( "Equation you need:  ------ Converting 20 minutes to an hour(s)
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document.write( "3(240)(S + 10) - 3(240S) = S(S + 10) ------- Multiplying by LCD, 3S(S + 10)
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document.write( "\"matrix%281%2C3%2C+720S+%2B+%227%2C200%22+-+720S%2C+%22=%22%2C+S%5E2+%2B+10S%29\"
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document.write( "\"matrix%281%2C3%2C+S%5E2+%2B+10S+-+%227%2C200%22%2C+%22=%22%2C+0%29\"
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document.write( "Factors of the above TRINOMIAL: + 90 and - 80
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document.write( "Original speed or \"highlight_green%28matrix%281%2C4%2C+S%2C+%22=%22%2C+80%2C+%22km%2Fh%22%29%29\"       OR   S = - 90 km/h (ignore) \n" );
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