SOLUTION: Solve this inequalty:3x - 2y > -12

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Question 72106: Solve this inequalty:3x - 2y > -12
Answer by Earlsdon(6294) About Me  (Show Source):
You can put this solution on YOUR website!
To solve linear inequalities with two variables, you can use graphing.
First solve the inequality for the y-variable.
3x-2y+%3C+-12 Add 2y to both sides.
3x+%3C+2y-12 Now add 12 to both sides.
3x%2B12+%3C+2y Finally divide both sides by 2.
%283%2F2%29x%2B6+%3C+y Now you graph this inequality by treating it like an equation and then graphing the linear equation.
But note that because the sign of the inequality is < the line on the graph should be a dashed line rather than a solid line. I don't know how to show a dashed lined.
So you will graph:
y+=+%283%2F2%29x%2B6
graph%28300%2C200%2C-5%2C5%2C-5%2C7%2C%283%2F2%29x%2B6%29
Now you need to shade the area of the graph that contains solutions to the inequality. For this you will need a "test point" or two to determine which side of the line to shade.
Let's try test point (0, 0) and put these values of x and y in the original inequality to see whether or not it is a solution.
3%280%29-2%280%29+%3E+-12
0+%3E+-12 This is true, so the point (0, 0) is a solution and should fall within the shaded area of the graph.
Now try a point on the other side of the line, (-5, 4)
3%28-5%29-2%284%29+%3E+-12
-15-8+%3E+-12
-23+%3E+-12 This is not true so the point (-5, 4) is not a solution and should fall on the un-shaded side of the line.
So, on the graph, you need to shade the area below and to the right of the "dashed" line.
This is the area that contains the solutions to the inequality.