document.write( "Question 526139: Could someone please explain to me step by step how to complete this problem? I am able to get to the part where you simplify but am not able to get no farther.
\n" ); document.write( "During the first part of a trip, a canoeist travels 91 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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Algebra.Com's Answer #348350 by ankor@dixie-net.com(22740)\"\" \"About 
You can put this solution on YOUR website!
During the first part of a trip, a canoeist travels 61 miles at a certain speed.
\n" ); document.write( " The canoeist travels 2 miles on the second part of the trip at a speed 5 mph slower.
\n" ); document.write( " The total time for the trip is 3 hours. What was the speed on each part of the trip?
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\n" ); document.write( "Let s = the speed for the 1st 61 mi
\n" ); document.write( "then
\n" ); document.write( "(s-5) = the speed for the last 2 mi
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\n" ); document.write( "Write a time equation, time = dist/speed
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\n" ); document.write( "faster time + slower time = 3 hrs
\n" ); document.write( "\"61%2Fs\" + \"2%2F%28s-5%29\" = 3
\n" ); document.write( ":
\n" ); document.write( "multiply by s(s-5), results:
\n" ); document.write( "61(s-5) + 2s = 3s(s-5)
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\n" ); document.write( "61s - 305 + 2s = 3s^2 - 15s
\n" ); document.write( "63s - 305 = 3s^2 - 15s
\n" ); document.write( "Arrange as a quadratic equation on the right
\n" ); document.write( "0 = 3s^2 - 15s - 63s + 305
\n" ); document.write( "3s^2 - 78s + 305 = 0
\n" ); document.write( "Use the quadratic formula to find s:
\n" ); document.write( "\"x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+\"
\n" ); document.write( "In this problem, a=3, b=-78, c=305, x=s
\n" ); document.write( "\"s+=+%28-%28-78%29+%2B-+sqrt%28-78%5E2-4%2A3%2A305+%29%29%2F%282%2A3%29+\"
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\n" ); document.write( "\"s+=+%2878+%2B-+sqrt%286084-3660+%29%29%2F6+\"
\n" ); document.write( ":
\n" ); document.write( "\"s+=+%2878+%2B-+sqrt%282424%29%29%2F6+\"
\n" ); document.write( "Two solutions
\n" ); document.write( "\"s+=+%2878+%2B+49.234%29%2F6+\"
\n" ); document.write( "s = \"127.234%2F6\"
\n" ); document.write( "s = 21.206
\n" ); document.write( "and
\n" ); document.write( "\"s+=+%2878+-+49.234%29%2F6+\"
\n" ); document.write( "s = \"28.766%2F6\"
\n" ); document.write( "s = 4.794
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\n" ); document.write( "Obviously the only reasonable solution:
\n" ); document.write( "s = 21.206 mph on the first 61 mi
\n" ); document.write( "and
\n" ); document.write( " 16.206 mph on the last two miles
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\n" ); document.write( "See if that check out, find the actual time of each
\n" ); document.write( "61/21.206 = 2.876 hrs
\n" ); document.write( "2/16.206 = .123 hrs
\n" ); document.write( "----------------------
\n" ); document.write( "total time: 3.0 hrs
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