Here are a few vids on the Quadratic Equation itself. How to derive it and why it looks like it does. There will be a couple of more short vids on this topic, but for now here are three.
This first vid really needs redoing because you can't always see the symbols and I left off the x in the middle term when I copied it at one point...but good enough for now...
The second EASIER way:
The third and hardest way:
Look for more shortly. Here is a webpage on the quadratic formula at the house of math...
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