SOLUTION: graph y= 1/2x-4

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Question 1205208: graph y= 1/2x-4
Found 3 solutions by MathLover1, josgarithmetic, Edwin McCravy:
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!

Graph y=%281%2F2%29x-4
make table
x|y
0|-4....y=%281%2F2%29%2A0-4=>y=-4
8|0....0=%281%2F2%29x-4=>%281%2F2%29x=4=>x=8


Answer by josgarithmetic(39618) About Me  (Show Source):
You can put this solution on YOUR website!
Like all of these you asked, the equation is in slope-intercept form so you can read from it the slope (1/2) and the y-axis intercept (0, -4), and you have enough to make the graph.

Plot the point. Use the slope for any other point or points you want. Draw the line through the points.

Answer by Edwin McCravy(20056) About Me  (Show Source):
You can put this solution on YOUR website!
I think I'll just change to other one I posted for this student.


The other tutor showed one way to graph the line, but I think you may just
be starting graphing lines from their equations, and you need this more
elementary method:

y=expr%281%2F2%29x-4. That is in slope-intercept form y=mx%2Bb

Some teachers teach it this way: "b" stands for "BEGIN" and "m" stands 
for "MOVE".  You BEGIN at the y-intercept, and then you MOVE from there, 
as described below:

the slope is m=1%2F2 and the y-intercept is b=-4.  The 
y-intercept, b, means that we BEGIN where the line intersects the y-axis
at the point (0,b), which in this case is the point (0,-4).
[That's where you "BEGIN". (Think of "b" as if it stood for "BEGIN".)

So we mark the y-intercept point (0,-4), like this:



Now we MOVE from the y-intercept (0,-4):

1. The slope is positive so this means from that point we go UPWARD the NUMERATOR of
the slope. (When the slope is negative we go DOWN, but in this case we go UP).

The NUMERATOR of the slope, 1%2F2 is 1, and positive, so we draw the line
segment UPWARD from
the y-intercept). So we draw a line segment from the y-intercept (0,-4) up 1
unit, from (0,-4) to (0,-3), like this:

 

2. Now from there, at the point (0,-3), we draw a line TO THE RIGHT (ALWAYS to
the RIGHT) the DENOMINATOR of the slope, which is 2 units RIGHT.  It goes from
the point (0,-3) to the RIGHT to the point (2,-3), like this:

 

Finally we draw a line, through the point we BEGAN at (0,-4), and the point we
MOVED TO or ended up at, (2,-3), and that is the graph of the line whose
equation is y=expr%281%2F2%29x-4.



You should LEARN: 
1. that a line which has a POSITIVE number for its slope, always
leans to the RIGHT, like this one, and a line which has a NEGATIVE number for
its slope always leans to the LEFT.  
2. that the GREATER the (absolute value) of the slope, the STEEPER the line.
3. if the slope is 1 or -1, the line is at an angle of 45o.
If the slope is a fraction or number less than 1, it is LESS STEEP than 45o and 
if the slope is a fraction or number greater than 1, it is STEEPER than 45o.

Edwin