Just a reminder that if you have an inequality and have to divide by a negative number to isolate x, don't forget to switch the direction of the sign!
Here's an example:
-2x>10
Well, you'd divide both sides by negative 2, right? That would give you that 2 is greater than negative 5. Hmmm. Let's try plugging in a number. Okay, what's something greater than negative 5? How about 100. Okay, plugging that in yields -200>10. Is that correct? No, of course not. This is why you need to switch the sign, so for example when you have
-2x>10
Divide both sides by -2 and SWITCH THE DIRECTION OF THE INEQUALITY
This will leave you with
x<-5
Let's try plugging in a number for x now that is less than negative 5. How about-20.
-2 (-20)>10
Is this true? Yes, indeed!
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