document.write( "Question 1151632: A boat’s speed in still in water is 4km/h.The boat cruises from A to B along a river flowing at an average speed of X km/h in the direction A to B . If the distance AB is 5 km and the boat takes 2hr more on its return journey,determine x. Hence,find the total time taken for the whole journey. \n" ); document.write( "
Algebra.Com's Answer #773495 by MathTherapy(10552)\"\" \"About 
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\n" ); document.write( "A boat’s speed in still in water is 4km/h.The boat cruises from A to B along a river flowing at an average speed of X km/h in the direction A to B . If the distance AB is 5 km and the boat takes 2hr more on its return journey,determine x. Hence,find the total time taken for the whole journey.
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From A to B, the boat is travelling WITH the current, so its time to get from A to B is \"5%2F%284+%2B+x%29\"
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document.write( "On the return trip (B to A), the boat is travelling AGAINST the current, so its time to get from B to A is \"5%2F%284+-+x%29\"
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document.write( "We then get the following TIME equation: \"matrix%281%2C3%2C+5%2F%284+-+X%29+-+5%2F%284+%2B+X%29%2C+%22=%22%2C+2%29\"
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document.write( "\"matrix%281%2C3%2C+5%284+%2B+X%29+-+5%284+-+X%29%2C+%22=%22%2C+2%284+-+X%29%284+%2B+X%29%29\"
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document.write( "\"matrix%281%2C3%2C+20+%2B+5X+-+20+%2B+5X%2C+%22=%22%2C+2%2816+-+X%5E2%29%29\"
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document.write( "\"matrix%281%2C3%2C+10X%2C+%22=%22%2C+32+-+2X%5E2%29\"
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document.write( "\"matrix%281%2C3%2C+2X%5E2+%2B+10x+-+32%2C+%22=%22%2C+0%29\"
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document.write( "\"matrix%281%2C3%2C+X%5E2+%2B+5x+-+16%2C+%22=%22%2C+0%29\"
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document.write( "Using the quadratic equation or completing the square, 
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document.write( "Now, calculate those 2 times and you should get the total time of the round-trip. \n" );
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