Question 428493
Car A	x 	mph						
Car B	x+	10						
..								
They are going away from each other.								
								
So add up their speed.								
								
combined speed = x+		1	x	+	10			
(	2	x	+	10	) 			
Time = 	5	hours						
Distance =   	750	miles						
Distance = speed * time								
(	2	x		10	)*	5	=	750
10	x 	+	50	=	750			
10	x 	=	750	+	-50			
10	x 	=	700					
/	10							
x=	70	mph	Car A					
Car B	70	+	10	=	80	mph