<PRE><B>Question 805763</B>
During the first part of a trip, a canoeist travels 16 miles at a certain speed. The canoeist travels 3 miles on the second part of the trip at a speed 5 mph slower. The total time for the trip is 3 hours. What was the speed on each part of the trip?

16 miles ------- speed ----------x
3 miles----------speed-----------(x-5)

Time First part + time II part = 3

t=d/r

16/x  + 3/(x-5) =3

multiply equation by x(x-3)

16(x-5)+3x=3x(x-5)

16x-80+3x =3x^2-15x

3x^2-34x+80=0

Find the roots of the equation by quadratic formula							
			iiiii				
a=	3	,	b=	-34	,	c=	80
							
b^2-4ac=	1156	+	-960				
b^2-4ac=	196						
{{{	sqrt(	196	)=	14	}}}		
{{{x=(-b+-sqrt(b^2-4ac))/(2a)}}}							
{{{x1=(-b+sqrt(b^2-4ac))/(2a)}}}							
x1=(	34	+	14	)/	6		
x1=	8.00						
{{{x2=(-b-sqrt(b^2-4ac))/(2a)}}}							
x2=(	34	-14	) /	6			
x2=	3.33						
							
canoe   	speed	8 mph				
							
m.ananth@hotmail.ca							


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