SOLUTION: During the first part of a trip, a canoeist travels 88 miles at a certain speed. The canoeist travels 19 miles on the second part of the trip at a speed 5mph slower. The total time

Algebra ->  Quadratic Equations and Parabolas  -> Quadratic Equations Lessons  -> Quadratic Equation Lesson -> SOLUTION: During the first part of a trip, a canoeist travels 88 miles at a certain speed. The canoeist travels 19 miles on the second part of the trip at a speed 5mph slower. The total time      Log On


   

Question 471343: During the first part of a trip, a canoeist travels 88 miles at a certain speed. The canoeist travels 19 miles on the second part of the trip at a speed 5mph slower. The total time for the trip is 2 hrs. What was the speed on each part of the trip?
1.Speed of 1st part of the trip?
2.Speed of 2nd part of the trip?''.
Answer by mananth(16946) About Me  (Show Source):
You can put this solution on YOUR website!
speed in first part x mph
speed second part x -5 mph
Total rowing time 2 hours
Time first part 88 / x
Time second part19/(x-5)

Time first part + time second part = 2 hours

88/x + 19 /(x -5 ) = 2
LCD = ( x + 0 )* (x -5 )
multiply the equation by the LCD
we get
88*(x-5)+19x= 2
88x-440 +19x=2X^2-10
117x-440=2X^2
2 X^2 -117 x 440 = 0
2 X^2+ -117 x+ 440 =
/ 2
1 X^2 -58.5 x 220 =

Find the roots of the equation by quadratic formula

a= 1 b= -58.5 c= 220

b^2-4ac= 3422.25 - -880
b^2-4ac= 2542.25
sqrt%28%092542.25%09%29= 50.42
x=%28-b%2B-sqrt%28b%5E2-4ac%29%29%2F%282a%29
x1=%28-b%2Bsqrt%28b%5E2-4ac%29%29%2F%282a%29
x1=( 58.5 + 50.42 )/ 2
x1= 54.46 54 4/9
x2=( 58.5 -50.42 ) / 2
x2= 4.04 4
Ignore value
x = 54.46 mph
m.ananth@hotmail.ca