Question 546884
Let the number be xy
x in the tens place and y in units place


1	x	+	1	y	=	13	.............1
-9	x	+	9	y	=	27	.............2
9	y						
multiply (1)by 		9					
Multiply (2) by		-1					
9	x		9	y	=	117	
9	x	+	-9	y	=	-27	
Add the two equations							
18	x				=	90.000	
/	18						
x	=	5					
plug value of 			x	in (1)			
1	x	+	1	y	=	13	
5		+	1	y	=	13	
			1	y	=	13-5	
			1	y	=	8	
				y	=	8