Question 1172777
<pre>
I am assuming you are in the early stages of learning Algebra.  Here are the
detailed steps:

2x - 4y = 8

To rearrange an equation, we make use of this basic fact: if you perform the
same allowed operation to both sides of the equation, you maintain equality.
If A=B then A+2 = B+2, A/2 = B/2, etc...  


I. Subtract 2x from both sides (the '2x' goes away on left hand side (LHS)):

2x -4y -2x = 8 - 2x
   -4y     = 8 - 2x   (see how LHS has 0x ('zero' times x))


II. Divide both sides by -4:
   -4y/(-4) = (8 - 2x)/(-4)    (LHS becomes 'one' times y, which is written simply as 'y')
     y      = -2x/(-4) + 8/(-4) 
     {{{    highlight(y      = (1/2)x - 2) }}}   

This is in the form y = mx + b    
   m is the slope (rise / run) and here it is 1/2
   b is the y-intercept, it is where the line meets the y-axis and is
         -2 in this case.   Note that the y-axis is where x=0, so if you
         set x=0 in y=mx+b you get y=b.  Hope this makes sense(?)

{{{ drawing(400,400, -10,10,-10,10, grid(0),
     line(-10,-7,10,3),

     locate(4,3,"y=(1/2)x - 2"),
     line(0,-2,0.5,-2),
     locate(1.0,-1.8, "b = -2")

)}}}