Question 295714: do you change the sign when dividing by an negative or du you do it before
Found 2 solutions by PRMath, Fombitz:
Answer by PRMath(133)   (Show Source):
You can put this solution on YOUR website! Do you change the sign when dividing by an negative or do you do it before?
This is a confusing question, because I'm not sure the type of problem you are referring to, given that there are many instances where you divide by a negative.
For example, consider these rules:
A positive divided by a negative is a negative.
A negative divided by a negative is a positive.
In those cases, you are changing the sign.
If you are talking about inequalities, then you "flip" the sign when you divide by a negative.
For example, you could solve for "X" in the problem below, and you'd have to flip the sign because you are dividing by a negative. See the following:
-2x < 6
x > -3 (see how the sign flipped when we divided by -2? And see how the answer became -3 because we divided a positive by a negative?)
Here's another example:
-3y > -9
y < 3 (Again, the sign flipped because we divided by a negative. BUT, -9 divided by -3 gives a +3, so the answer was positive, which is also a changed sign).
If you give a sample question, you may get a little more help. I hope this helps you tho. :-)
Answer by Fombitz(32388)  (Show Source):
You can put this solution on YOUR website! Any time you multiply or divide an inequality by a negative number, you change the direction of the inequality (at the same time).
|
|
|
