SOLUTION: please help: 6x-4y<-12 Graph the linear inequality

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Question 161960: please help: 6x-4y<-12 Graph the linear inequality
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
In order to graph 6x-4y%3C-12, we need to graph the equation 6x-4y=-12 (just replace the inequality sign with an equal sign).
So lets graph the line 6x-4y=-12

+graph%28+500%2C+500%2C+-20%2C+20%2C+-20%2C+20%2C+%283%2F2%29x%2B3%29+ graph of 6x-4y=-12

Now lets pick a test point, say (0,0). Any point will work, (just make sure the point doesn't lie on the line) but this point is the easiest to work with. Now evaluate the inequality 6x-4y%3C-12 with the test point

Substitute (0,0) into the inequality

6%280%29-4%280%29%3C-12 Plug in x=0 and y=0

0%3C-12 Simplify






Since this inequality is not true, we do not shade the entire region that contains (0,0). So this means we shade the region that is on the opposite side of the line. In other words, simply shade the ENTIRE region above the line.

Graph of 6x-4y%3C-12 with the boundary (which is the line 6x-4y=-12 in red) and the shaded region (in green)
(note: since the inequality contains a less-than sign, this means the boundary is excluded. This means the solid red line is really a dashed line)