Tuesday, May 5, 2009

A Simple Theorem

if Ax + b = 0, then x = -b/a

This is not a huge surprise. They probably teach this to high school kids.

But until today, when faced with an equation like the one above, I would do it step by step, like so:

2x + 3 = 0
2x = -3
x = -3/2

Of course I'm not a yukel. I noticed that the constant term always ended up being the numerator and that the coefficient ended up being the denominator. I just never thought about it long enough to start using a formula to solve equations instead of the step-by-step approach.

So I guess the point of this post is that today I thought of something which there's no excuse for me not thinking of before.


  1. Well I do it step by step too... just really fast...

  2. If you do it step by step really fast, you might make a mistake, like forgetting to flip the sign of the constant term. Hence the benefit of this formula.

  3. No in your head if you know basic algebra it's not an issue....


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