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Solve for C and graph the solution. We have have -5C is less than or equal to 15. So -5C is less

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than or equal to 15. I just rewrote it a little bit bigger. So if we want to solve for C, we just want

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to isolate this C right over here, maybe on the left -hand side. Its right now being multiplied by -5

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So the best way to just have a C on the left-hand side is we can multiply both sides of this inequality

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by the inverse of -5 or by -(1/5). So we want to multiply -(1/5)

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times -5C and we also want to multiply 15 times - (1/5). I'm just multiplying both

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sides of the inequality by the inverse of -5, because this will cancel out with -5 and will leave

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me just with C. Now I didn't draw the inequality here, because we have to remember if we multiply or

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divide both sides of an inequality by a negative number, you have to flip the inequality and we are doing

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that. We are multiplying both sides by -(1/5), which is the equivalent of dividing both sides

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by -5. So we need to turn this from a less than or equal to a greater than or equal. And now we can proceed

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solving for C. So -(1/5) times -5 is 1, so the left-hand side is just going to be

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C is greater than or equal to 15 times -(1/5). That's the same thing as 15 divided

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by -5. And so that is -3. So our solution is C is greater than or equal to -3

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and let's graph it. So that is my number line. Let's say that is 0, -1, -2, -3 and that can go above

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1 too. And so C is greater than or equal to -3, so it can be equal to -3, so I'll fill that in right

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over there. Let me do it in a different color. So I'll fill it in right over there and then its greater

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than as well. So its all of these values I am filling in in green. And you can verify that it works in

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the original inequality. Pick something that should work. Well 0 should work. 0 is one of the numbers

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that we filled in. -5 times 0 is 0, which is less than or equal to 15, its less than 15. Now let's try

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a number that's outside of it. And I haven't drawn it here, I could continue with the number line in

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this direction. You would have a -4 here. -4 should not be included and let's verify that -4 doesn't

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work. -4 times -5 is +20 and +20 is not less than 15 so its good that we did not include -4.

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So this is our solution and this is that solution graphed. And I wanted to do that in the other green color.

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Here you go, that's what it looks like.