<PRE><B>Question 474472</B>
-1	x		-3	y	=	-20	.............1				
3	y	=	40		-5	x	---------2				
/	3	=									
	y	=	13.33		-1.67	x					
Substitute y in 		(1)									
-1x-3(13.33-1.67x)=-20
-1x-40+	5x=-20			
-1x+5x	=-20+40				
4x=20								
/	4										
x=	5										
Plug the value of x in (1)											
-1	x		-3	y	=	-20					
-1	*	5		-3	y	=	-20				
-5-3y=-20						
-3y=-15								
/-3										
y=5										
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