Thread: Formula Rearrange

Hi,

I am generally not too bad at rearranging formulas, but the result I have for the below differs from that which my colleague has calculated. Other opinion(s) would be very much appreciated.
If possible a couple of intermediate steps would be useful for my understanding.

The equation is below and I would like to solve for X



When I rearrange i get:



[that is a B by the root sign]


I would very much appreciate another interpretation.


Regards

(I hope this is the correct forum I did think about it!)

We have , from where , and .

Thanks very much for the response.

Would it be possible to explain 2 of the steps?:

First step: how does "(y - D)" become the denominator as opposed to just "y"

Last step: How (A - D)/(y - D) becomes (A - y)/(y - D)


i apologise if I am being a bit thick here.


Regards

Originally Posted by UberTyson

First step: how does "(y - D)" become the denominator as opposed to just "y"

In your version, the denominator is also y - D. We start from , subtract D from both sides to get , from where (just like 5 = 10 / 2 is equivalent to 2 = 10 / 5).

Originally Posted by UberTyson

Last step: How (A - D)/(y - D) becomes (A - y)/(y - D)

It's not just (A - D)/(y - D), but (A - D)/(y - D) - 1. Represent 1 as (y - D) / (y - D); now you have the same denominator, and A - D - (y - D) = A - y.

Originally Posted by UberTyson

Thanks very much for the response.

Would it be possible to explain 2 of the steps?:

First step: how does "(y - D)" become the denominator as opposed to just "y"

Let's start from the beginning:

Last step: How (A - D)/(y - D) becomes (A - y)/(y - D)

...

I'll take only the radicand:




EDIT: This is a wonderful example of an unnecessary reply. Sorry, emakarov, I didn't see that you were online.

Thank you both for your help it is now clear in my mind. Makes me feel stupid when you solve it so easily!

Appreciate the help,

Regards