Question 548161
plane speed	speed	=x	mph						
wind 	speed	=y	mph						
against wind , x-y		5	hours						
with wind , x+y		4	hours						
									
Distance = same=		2000	miles						
t=d/r	against	wind 							
2000/(x-y)=5.00		
5(x-y)=2,000.00		
With	wind 							
5x-5y=2000	....................1		
2000/(x+y)=4.00		
4.00(x+y)=2000		
4.00x+4y=2000	...............2		
Multiply (1) by 	4.00								
Multiply (2) by	5.00								
we get									
20	x	+	-20	y	=	8000			
20	x	+	20	y	=	10000			
40	x	=	18000						
/	40								
x 	=	450	mph						
									
plug value of x in (1)									
5	x		-5	y	=	2000			
2250			-5	y	=	2000			
-5	y	=	2000	-2250					
-5	y	=	-250						
	y	=	50	mph					
	plane speed	450	mph						
	wind 	50	mph						
									
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