document.write( "Question 162664: During the first part of a trip, a canoeist travels 69 miles at a certain speed. The canoeist travels 2 miles on the second part of the trip at a speed 5 mph slower. The total time for the trip is 3 hrs. What was the speed on each part of the trip? \n" ); document.write( "
Algebra.Com's Answer #119893 by ankor@dixie-net.com(22740)\"\" \"About 
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During the first part of a trip, a canoeist travels 69 miles at a certain speed. The canoeist travels 2 miles on the second part of the trip at a speed 5 mph slower. The total time for the trip is 3 hrs. What was the speed on each part of the trip?
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\n" ); document.write( "Canoing that far in 3 hrs is a fantasy, but anyway:
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\n" ); document.write( "Let s = speed on the 69 miles
\n" ); document.write( "then
\n" ); document.write( "(s-5) = speed on the last to miles of the trip
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\n" ); document.write( "Write a time equation: Time = dist/speed
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\n" ); document.write( "69 mi time + 2 mi time = 3 hrs
\n" ); document.write( "\"69%2Fs\" + \"2%2F%28%28s-5%29%29\" = 3
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\n" ); document.write( "Multiply equation by s(s-5), results:
\n" ); document.write( "69(s-5) + 2s = 3s(s-5)
\n" ); document.write( "69s - 345 + 2s = 3s^2 - 15s
\n" ); document.write( "71s - 345 = 3s^2 - 15s
\n" ); document.write( "0 = 3s^2 - 15s = 71s + 345
\n" ); document.write( "A quadratic equation:
\n" ); document.write( "3s^2 - 86s + 345 = 0
\n" ); document.write( "Use the quadratic formula to solve this
\n" ); document.write( "The solution that makes sense is s ~ 23.84 mph for the 1st 69mi
\n" ); document.write( "and
\n" ); document.write( "23.84 - 5 = 18.84 mph for the last two mi
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\n" ); document.write( "Check solution by finding the times at each speed
\n" ); document.write( "69/23.84 = 2.89 hrs
\n" ); document.write( "2/18.84 = .106 hr
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\n" ); document.write( "total time 2.996 ~ 3 hrs
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\n" ); document.write( "I suspect there may be a typo in this as written here, but the method should
\n" ); document.write( "help you.
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