Question 500983
Plane   	speed	=x	km/h					
Wind   	speed	=y	km/h					
against wind x-y		5.00	hours					
with windx+y		4.00	hours					
								
Distance = same=		4400	miles					
t=d/r								
4400	/	(	x	-	y	)=	5.00	
5	(	x	-	y	)	=	4,400.00	
5	x		-5	y	=	4400	....................1	
4400	/	(	x	+	y	)=	4.00	
4.00	(	x	+	y	)	=	4400	
4.00	x	+	4.00	y	=	4400	...............2	
Multiply (1) by 	4.00							
Multiply (2) by	5.00							
we get								
20	x	+	-20	y	=	17600		
20	x	+	20	y	=	22000		
40	x	=	39600					
/	40							
x 	=	990	km/h					
								
plug value of x in (1)								
5	x		-5	y	=	4400		
4950			-5	y	=	4400		
-5	y	=	4400	-4950				
-5	y	=	-550					
	y	=	110	km/h