Question 415123
numbers be x, y
11+x=3y
x-3y=-11..............1
x-9 = 1/2 y
2(x-9)=y
2x-18=y
y-2x=-18..............2
...

x-3y=-11	.............1	
-2x+y	=-18	.............2	
								
multiply (1)by 					2	
Multiply (2) by					1	
2x-6y	=-22
-2x+y	=-18
						
Add the two equations						
						
-5y=-40
						
/-5					
						
y=8			
Plug value of y in 					
x-3y=-11
x-24=-11
x=13