document.write( "Question 638031: The distance between city A and B is 28 km. Two hikers left from each city (One from city A to city B and the other from city B to city A) heading towards each other at the same speed. The hiker from city A rested for an hour after having walked 9 km and then continued at a speed greater than 1 km/hour than his previous speed, then rested again 4 km away from city B. There he met the hiker from city B, who walked at a constant speed without resting until the two met. What were the speeds of the two hikers? \n" ); document.write( "
Algebra.Com's Answer #402276 by ankor@dixie-net.com(22740)\"\" \"About 
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The distance between city A and B is 28 km.
\n" ); document.write( "Two hikers left from each city (One from city A to city B and the other from
\n" ); document.write( " city B to city A) heading towards each other at the same speed.
\n" ); document.write( "The hiker from city A rested for an hour after having walked 9 km and then
\n" ); document.write( " continued at a speed greater than 1 km/hour than his previous speed, then
\n" ); document.write( " rested again 4 km away from city B.
\n" ); document.write( "There he met the hiker from city B, who walked at a constant speed without
\n" ); document.write( " resting until the two met.
\n" ); document.write( " What were the speeds of the two hikers?
\n" ); document.write( ":
\n" ); document.write( "Let s = speed of the two hikers
\n" ); document.write( "then
\n" ); document.write( "(s+1) = speed of the A after his 1 hr rest
\n" ); document.write( ":
\n" ); document.write( "Find the distance hiker A traveled after his rest, to meet B, 4 km from City B
\n" ); document.write( "28-9-4 = 15 km
\n" ); document.write( ":
\n" ); document.write( "Write a time equation; time = dist/speed
\n" ); document.write( "\"9%2Fs\" + \"15%2F%28s%2B1%29\" + 1 = \"4%2Fs\"
\n" ); document.write( ":
\n" ); document.write( "\"9%2Fs\" + \"15%2F%28s%2B1%29\" = \"4%2Fs\" - 1
\n" ); document.write( ":
\n" ); document.write( "\"%289%28s%2B1%29%2B15s%29%2F%28s%28s%2B1%29%29\" = \"%284-s%29%2Fs\"
\n" ); document.write( ":
\n" ); document.write( "\"%289s%2B9%2B15s%29%2F%28s%28s%2B1%29%29\" = \"%284-s%29%2Fs\"
\n" ); document.write( ":
\n" ); document.write( "\"%2824s%2B9%29%2F%28s%28s%2B1%29%29\" = \"%284-s%29%2Fs\"
\n" ); document.write( "Multiply both sides by s
\n" ); document.write( "\"%2824s%2B9%29%2F%28%28s%2B1%29%29\" = (4 - s)
\n" ); document.write( "24s + 9 = (s+1)(4-s)
\n" ); document.write( "FOIL the right side
\n" ); document.write( "24s + 9 = 4s - s^2 + 4 - s
\n" ); document.write( "24s + 9 = 3s - s^2 + 4
\n" ); document.write( "Combine on the left
\n" ); document.write( "s^2 + 24s - 3s + 9 - 4 = 0
\n" ); document.write( "s^2 + 21s + 5 = 0
\n" ); document.write( "Actually this equation has two negative solutions so the given scenario is not possible.
\n" ); document.write( "It seems unreasonable, to find a speed, where A travels 24 km (+ a rest),
\n" ); document.write( "while B travels 4 km
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