3x-2y=-39 and x+3y=31 solution using elimination

This is hard to write... I hope this makes sense to you...
3x-2y=-39
x+3y= 31
We want to use elimination therefor, we need to either get our x or our y to add together to get zero. 
To do this, we will multiply -3 to (x=3y=31) 
NEW EQUATION
3x-2y=-39 PLUS
-3x-9y= -93 Equals
-11y= -54 
y= 4.9
Plug in to solve for x (put new y in)
3x-2(4.9)=-39
x= -9.73 

Solving for x on 3x - 2y = -39:
First, we must add 2y to both sides.
3x - 2y + 2y = -39 + 2y
3x = 2y - 39
Next, we divide both sides by 3.
3x/3 = 2y - 39/3
2/3y - 13

Solving for y on x+3y=31:
First, we must add -x to both of the sides.
x + 3y + -x = 31 + -x
3y = -x + 31
Next, we must divide both sides by 3. (Like last time.)
3y/3 = -x + 31/3
y = -1/3x + 31/3

I hope this helps! (And what you're looking for! :>)

B. 2 1/2 feet. multiply 2.5 inches by 12 to get thirty inches then divide by 12 to get 2.5 feet