Free to download

Arithmetic

Negative terms.
>
negatives
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Long division.
>
long division
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Linear equations and systems

Not-obvious coefficients.
>
coefficients
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Quadratics

Simplifying an imaginary radical.
>
imaginary
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Squaring a binomial.
>
squaring-a-binomial
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Polynomials

Polynomial division.
>
polynomial division
Animations

Many more to come...

These are examples of what you will find here. Check back frequently as items will be added and re-organized over the next few months.