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| Question 110114:  graph by first solving for y
 x-3y=9
 
 x-9=3y divide both sides by 3
 x-3=y or would it be y=1/3x
 Am I on the right track and how do you graph a fraction?
 Found 2 solutions by  Edwin McCravy, stanbon:
 Answer by Edwin McCravy(20064)
      (Show Source): 
You can put this solution on YOUR website! 
graph by first solving for y    
   x - 3y = 9
get rid of the "x" term on the left by adding -x to both sides:
   x - 3y = 9
  -x          - x
---------------------
      -3y = 9 - x
Now divide every term by -3:
 =  -  Simplify:  =  +  This is now solved for y. Next we have to 
get some points on the line.
Arbitrarily pick any convenient number to substitute
for x.  I think I will first choose 0 to substitute
for x.  I chose 0 simply because it is easy.  So we 
substitute x = 0  =  +    =  +    =  +    =  So one point on the first line is (x, y) = (0,-3) 
Let's plot that point.  That point is on the
y-axis where y = -3  Now for the second point on the line, I think I will 
choose 3 to substitute for x.  I chose 3 simply because 
the term  will be  or  so it
won't be a fraction.  I could have chosen any other 
number, but I can avoid fractions by choosing whole
numbers for x that are divisible by 3. So we substitute
x = 3  =  +    =  +    =  +    =  So another point on the first line is (x, y) = (3, -2)
Now let's plot that point. It is directly below 3 on
the x axis and directly to the right of -2 on the
y axis:  We could draw a line through those two points.
However to be on the safe side, we should get
a third point. 
Now for the third point on the line, I think I will 
choose -6 to substitute for x.  I chose -6 simply because 
the term  will be  or  so it
won't be a fraction.  I could have chosen any other 
number, but, as before, I can avoid fractions by choosing
whole numbers for x that are divisible by 3. So we 
substitute x = -6  =  +    =  +    =  +    =  So another point on the first line is (x, y) = (-6, -5)
Now let's plot that point. It is directly below -6 on
the x axis and directly to the left of -5 on the
y axis:  Now we draw a straight line through all three
points.  That's the graph of the equation
   x - 3y = 9
EdwinAnswer by stanbon(75887)
      (Show Source): 
You can put this solution on YOUR website! graph by first solving for y x-3y=9
 x-9=3y divide both sides by 3
 x-3=y or would it be y=(1/3)x-1
 ----------------
 Plot two points and draw a line thru them:
 If x=0 y=-1
 If x=3,y=0
 ----------
 Plot the points (0,-1) (3,0)
 ----------------------
 Graph:
 
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 Cheers,
 Stan H.
 
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