Question 417857
let the numbers be x, y, z

2x=y+z+11
2x-y-z=11

2x+3z=y+1
2x-y+3z=1

y=x+z
-x+y-z=0

2x-y-z=11--------------	1
2x-y+3z	=1--------------2
-x+y-z=	0--------------	3
																
consider equation 1 &2															
Multiply 1 by	-1								
Multiply 2 by	1								
we get															
-2x+y+z	=-11					
2x-y+3z	=1					
Add the two 															
4z=-10	-------------4
z==-2.5
consider equation 2 & 3															
Multiply 2 by 1											
Multiply 3 by 1											
	we get															
2x-y+3z	=1						
-x+y+-z	=0						
	Add the two 															
1x+2z=	1-------------5	
plug value of z
x-5=1
x=6
plug value of x & z in 1

12-y+2.5=11
y=3.5