Deriving the Quadratic Formula

You can optionally see also and for what is completing square.

I will show alternative way to accomplish this task.


So, the tough question will be






x+(3/2)=(1/2) or x+(3/2)=-(1/2)

x=-1 or x=-2

And so, alternative derivation would be:

We want to solve

ax²+bx+c=0, where a≠0

Because a≠0 we can divide both parts by a, we will get




or another way around




(x+(b/2a))=± sqrt((b²-4ac)/4a²)

From here:

(x+(b/2a))=± (sqrt(b²-4ac)/2a)

x=-(b/2a)± (sqrt(b²-4ac)/2a)

After, you know the formula, solving the tough question will be much easier:



Originally published in my blog

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