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Science-Related Homework Help Mathematics Topic started by: smmcmahon35 on Oct 28, 2012



Title: What is the correct way to divide a equation or inequality?
Post by: smmcmahon35 on Oct 28, 2012
When I ask this I mean, would it be correct if I put a whole equation or inequality in parenthesis and then divided just curious?
For an example:
(2x=4)÷(2) or (2x>4)÷(2)  

I am dividing each side by 2 but when doing so am I supposed to write it as a fraction or would it be ok like that? The reason I want to know is because if I am asked to show my work I don't want points tooken off for this.
Sorry taken not tooken


Title: What is the correct way to divide a equation or inequality?
Post by: leolena on Oct 28, 2012
Sure, it's fine.  Most people don't write it that way, but it's not wrong.  Usually people would divide each side separately by 2, but the effect is the same, as long as you communicate what you're doing, it shouldn't matter.


Title: What is the correct way to divide a equation or inequality?
Post by: dattallmofo_ on Oct 28, 2012
When you mutiply or divide an equation (because they're basically the same operation) and you just do the same thing to both sides.

So, you'd set it out something like this.

2x = 4.  
x = 2 (Divide both sides by two)

If it's obvious what you're doing, you can omit the brackets, but if you're not sure, leaving them in probably doesn't hurt.

As for ineqations, it's pretty much the same.

2x > 4
x > 2 (Divide both sides by 2)

etc.

Just be careful when dividing (or multiplying) by negates, be sure to swap the sign around.

You could also do something like this:

2x = 4.  
x = 2 (÷2)

I would avoid trying to preform some operation on a whole equation like that. People often talk about multiplying equations, etc, but It's not technically something you're supposed to do, it's more of a short hand for saying that something will be done to both sides of an equation.

Also, I've never seen A fraction live (a=b)/2 so you're better off just writing a/2 = b/2.
You can never really be "wrong" in aesthetic cases like this, as long as you arrive at a correct answer in the end, but there are preferred ways to set things out, and I would reccomend abiding by those standards, in the long run it;ll make things a lot easier.