Question 429869
1	x	+	-1	y	=	121	.............1		
-1	x	+	6	y	=	4	.............2		
Eliminate y									
multiply (1)by 		6							
Multiply (2) by		1							
6	x	+	-6	y	=	726			
-1	x	+	6	y	=	4			
Add the two equations									
5	x				=	730			
/	5								
x=146 	=146.00			
plug value of 	x in (1)					
x-y	=	121			
146-y=121			
			-1	y	=	121	+	-146	
			-1	y	=	-25			
				y	=	25