# Factor Out the Greatest Common Factor (GCF)

Learn how to factor out the greatest common factor (GCF).

In this video, we are going to look at how to factor out the greatest common factor.
For example:
To factor:
$x^2+5x$
we can factor out a variable, x, by dividing it out of each term, leaving us with
$x(x+5)$
To factor:
$3y^4+6y^3+12y^2$
the largest number we can pull out from all of the terms is 3, and the largest variable is $y^2$. So if we factor out $3y^2$ then we would be left with
$3y^2(y^2+2y+4)$
To factor:
$8x^3y^2+24x^4y-20x^2y^2$
the largest number that can be pulled out is 4, the largest variable in terms of x is $x^2$, and the largest variable in terms of y is just y. So if we factor out $4x^2y$then we would be left with
$4x^2y(2xy+6x^2-5y)$

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