Question 471343
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(	2542.25	)}}}=	50.42							
{{{x=(-b+-sqrt(b^2-4ac))/(2a)}}}														
{{{x1=(-b+sqrt(b^2-4ac))/(2a)}}}														
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