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I'm just going through some notes on linear interpolation, but this bit has got me confused - I think it's an easy work through on gradients etc, but my maths seems to be failing me (mature student here so go easy on me :shy: )

Ok here goes (see attached images - not sure about latex yet. A look at image 2 first, it just shows the gradient equation)

My question is: How can e.g. (x2-x) become (x-x2), I was always taught that when you move the lower part of a division/fraction to the other side of the equals sign, you don't change it! So, how does this work?

Is there some trick that occurs when you rearrange an equation or is there some maths rule that I was never taught.

I know this is probably a solve in 2 seconds type question, but it's starting to bug me now !!:grumpy:

Cheer

Kel

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# Fairly basic algebra question - but it's bugging me now!

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