Question 918081
Forward 	speed	x															
return 	speed	x	+	10													
																	
	Distance = same		150	miles	1												
	original time – time with increased speed =					2.5	hour										
	t=d/t																
																	
	150	/	x	-	150	/	(	x	+	10	)	=	2.50				
	LCD=	x	(	x	+	10	)										
	multiply by LCD																
	150	(	x	+	10	)	-	150	x	=	2.5	x	(	x	+	10	)
	150	x	+	1500	-	150	x	=	2.5	X^2	+	25	x				
	1500	=	2.5	X^2	+	25	x										
	2.5	X^2		+	25	x	-	-1500	=	0							
	Find roots of the quadratic equation																
	a=	2.5		b=	25		c=	-1500									
																	
	x1=	(	-25	+	sqrt(		625	+	15000	))	/	5					
	x1=(	-25	+	125	)/	5											
	x1=	20															
																	
	x2=	(	-7	-	sqrt(		49	-	20	)	/	2					
	x2=(	-25	-	125	)/	5											
	x2=	-30															
Ignore negative

forward speed = 20 kmph
return speed = 30 kmph