Multiplying Binomials (Special Cases)

In this video, we are going to look at how to multiply special cases of binomials.
For example:
To multiply $(x+b)^2$ we have to multiply the binomial by itself. When we foil it, we get
$x^2+bx+bx+b^2$
After combining like terms, this simplifies to
$x^2+2bx+b^2$
By following this form, we can use this to solve any squared binomial.
For example:
$(x+4)^2$
can be solved by plugging in 4 for where we see b. This will give us a final answer of
$x^2+8x+16$
Another special case example would be to multiply $(x+b)(x-b)$
When we foil it we get
$x^2-bx+bx-b^2$
After combining like terms, it simplifies to
$x^2-b^2$
By following this form, we can use this to solve other binomials written this way.
For example:
$(x+4)(x-4)$
would be easily solvable by plugging in 4 for where we see b. This will give us a final answer of
$x^2-16$

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Used by students across the country. Pre-Algebra, Algebra I, Geometry, & Algebra II