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adrianosterman
Aug 14, 2010, 07:26 PM
need to find value h. 590h=300h+330000

KISS
Aug 14, 2010, 07:49 PM
You had to be asleep in class.

Get h to one side.

You'll end up with [so many]h = [some number]
That's like 3x =9
That's way too simple.

So what if the numbers are big.

What if this was 10h=3h+30

Could you do the problem?

adrianosterman
Aug 14, 2010, 08:17 PM
If I said I was asleep would you explain for me please. Im old and its been ages since I saw this sort of thing...

KISS
Aug 14, 2010, 08:58 PM
OK, I'll give you the EASY way out: 590x=300x+330000 - Wolfram|Alpha (http://www.wolframalpha.com/input/?i=590x%3D300x%2B330000)

I had to change h to x for it to work.

If you want me to solve it manually I'll be happy to.

morgaine300
Aug 15, 2010, 12:27 AM
What is the point of the easy way out? No one learns anything from that.

I'll run an example through:
25x\ = \ 15x\ +\ 5

The idea is to get the variable isolated, which requires that you both get any variables separated together, and also get rid of the coefficient. (Coefficient --> number on the x, the 25 and 15 being coefficients.)

So first let's get the x's on the same side. The 5 is a constant (no variable on it) and we want to leave that by itself on one side, so the one I'm going to move is the 15x on the right side. Keep in mind that whatever you do to one side you must do to the other side. And to get rid of something, you do the opposite operation. Since the 10x is a positive, I have to do a negative (i.e. subtract), and I have to subtract from both sides to keep the equation equivalent:

25x\ \underline{-\ 15x}\ =\ 15x\ \underline{-\ 15x}\ +\ 5

The "15x - 15x" on the right side just cancels out. That is, 15x - 15x = 0, which equals nothing and just goes away. So we now have:

25x\ -\ 15x\ =\ 5

Now we can combine the 25x and 15x by just subtracting the coefficient:

10x\ =\ 5

Now that we have all x's together, and isolated on one side, we can now get rid of that 10. Since that's a multiplication, we do the opposite operation to get rid of it: divide. And remember to do the same thing to both sides:

\frac{10x}{10}\ =\ \frac{5}{10}

The 10's on the left just cancel out. That's cause 10 divided by 10 = 1, and 1 times anything is itself. So 1x = just x. So we can simply "cancel out" the 10's.

x\ =\ \frac{5}{10}

The right side reduces to 1/2 but that's not really relevant to the process of getting there. That was just me trying to make an example and ending up with one with a fraction. :D

Is this for homework - did you go back to school? Or something you need to solve just for something you're doing? I'm only asking cause we're not really supposed to just give an answer to homework, but if it's just something you're doing we can certainly just give an answer away. But maybe it would be nice to learn how to do it again as well?

adrianosterman
Aug 15, 2010, 03:52 AM
This was for a project I'm doing at home. Im making a type of fishing net and needed to work out some cone templates. This was part of that. Thank you I have now learnt something new!