SOLUTION: graph inequality 2x<3y+6

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Question 328718: graph inequality 2x<3y+6
Found 2 solutions by Edwin McCravy, vleith:
Answer by Edwin McCravy(20056) About Me  (Show Source):
You can put this solution on YOUR website!

2x%22%22%3C%22%223y%2B6

Plot the graph of the equation formed by replacing the < by =

2x%22%22=%22%223y%2B6 

Get some points:

 x |  y
 0 | -2
 3 |  0
 6 |  2
-3 | -4

Draw the line dotted since the inequality is < and not <



One side of that dotted line will be shaded, because all the solutions are on
one side of that line and none are on the other side.

Choose a test point which is not on that line, substitute it in original
inequality to find out whether it is a solution or not.  If it is a solution,
then shade the side the test point is on. (That's because if one point on that
side is a solution then they all are.)  If it is not a solution, then shade
the other side of the line.

Let's arbitrarily choose (0,0,) as a test point.  Substitute x=0 and y=0 in
the original inequality:

2x%22%22%3C%22%223y%2B6
2%280%29%22%22%3C%22%223%280%29%2B6
0%22%22%3C%22%220%2B6
0%22%22%3C%22%226

That is true so the test point (0,0) is a solution, so we shade
the side of the line which the point (0,0) is on.  I can't shade on
here, but you can on your paper.  Shade the whole upper (left) side 
of the dotted line.  (The line was dotted to show that none of the
solutions lie on the line itself.)



Edwin



Answer by vleith(2983) About Me  (Show Source):
You can put this solution on YOUR website!
2x%3C3y%2B6
2x-6%3C+3y
2x%2F3+-2+%3C+y
Now plot the line 2x%2F3-2+=+y
Since this is a pure inequality (no equal sign) draw that line using a dashed line.
Then color in the area above that dashed line - above because of the < sign tells you to use all y that are "greater than" that line
See this URL for a plot
http://www.wolframalpha.com/input/?i=2x%3C3y%2B6