what does the graph of -3x-5y is greater than or equal to 20 look like? please help.

Question

anonymous · Answer

$$-3x-5y \ge20$$

zepdrix · Answer

$$\Large\rm -3x-5y\ge 20$$Ummm I always find these easier to work with if you put them in slope-intercept form.
Add 3x to each side,$$\Large\rm -5y\ge 3x+20$$Divide each side by -5,$$\Large\rm y\le -\frac{3}{5}x-4$$
y-intercept of -4,
negative slope.

zepdrix · Answer

So something like this,|dw:1404866807314:dw|

zepdrix · Answer

So let's deal with the inequality so we can get some shading and all that.

zepdrix · Answer

Oh oh back up a sec, do you understand why I FLIPPED the inequality sign?
We divided a negative across the inequality.

We have the `or equal to` included in our inequality,
so do we want a `solid` or `dashed` line?

anonymous · Answer

Yes I understand why you flipped the inequality.  What I am having trouble knowing is what makes the line be solid or dashed.  BTW, thanks for helping me.

zepdrix · Answer

$$\Large\rm y=-\frac{3}{5}x-4$$^This would be the line.
The inequality is also giving us shading on one of the sides.

See how the inequality has the `or equal to` on it?
That means we want to `include` the values along the line.

So it should be a SOLID line, we're including all those values.|dw:1404867096572:dw|