Welcome to an introduction to quadratic equations! This lesson hinges on the assumption that you, reader, already know the very basics: algebraic arithmetic, basic exponents, and the quadratic formula. If you do, then excellent! Let's move forward.
To begin with, all quadratic equations come in a form like this:
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Where a, b, and c are variables and x is another that you generally have to solve for. This equation equals to zero.
The first main topic you learn in A-level math under quadratic equations is the completion of the square. It relies on this expansion:
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Now, in case you don't know how this expansion comes about:
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Coming back to the topic - say we have a square with side length a.
The area of this square is going to be a x a, or a^2.
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