Question 934100
Car I	speed	x															
Car II	speed	x	+	-20													
																	
	Distance = same		480	miles	1												
	Car II time - Car I time = 2 hours	
	t=d/t																
																	
	480	/	x	-	480	/	(	x	+	-20	)	=	2.00				
	LCD=	x	(	x	+	-20	)										
	multiply by LCD																
	480	(	x	+	-20	)	-	480	x	=	2	x	(	x	+	-20	)
	480	x	+	-9600	-	480	x	=	2	X^2	+	-40	x				
	-9600	=	2	X^2	+	-40	x										
	2	X^2	-40	x	-	9600	=	0							
/2
x^2-20x-4800=0

x^2-20x+100= 4800+100

(x-10)^2= 4900

x-10 = 70  ( taking positive)

x= 80

Car I ------80 mph
Car II-------60 mph