Question 566516
-1	x	+	1	y	=	-9	.............1
1	x	+	8	y	=	0	.............2
Eliminate y							
multiply (1)by 		-8					
Multiply (2) by		1					
8	x		-8	y	=	72	
1	x		8	y	=	0	
Add the two equations							
9	x				=	72	
/	9						
x	=	8					
plug value of 			x	in (1)			
-1	x	+	1	y	=	-9	
-8		+	1	y	=	-9	
			1	y	=	-9	+8
			1	y	=	-1	
				y	=	-1