Factor using GCF

MooMooMath and Science
43 followers
96 Video Views·Jan 27, 2024
Learn how to factor using GCF Follow these steps.
Find the GCF
Divide by the GCF
Lead with the GCF
For example, Factor 48a^7 - 16a^5
How to find the GCF of monomials
welcome to mumo Math and Science in this
video let's talk about factoring using
the GCF and um let's just remember this
uh there's a couple steps and so
basically remember g d l you're going to
find the greatest common factor then
you're going to divide and then you're
going to lead with the greatest common
factor so let's get started with this
example and I'm going to move this up
and so here we
first thing we need to do is find the
greatest common factor of 4 A7 - 16 a
4th okay so I like to use a factor tree
in order to find the greatest common
factor so uh let's get started okay the
speed things along I went ahead and
completed a factor tree and I wrote
the um prime numbers in this box and the
rule is is since we have two numbers if
there's two in a column you bring it
down and then you multiply we do not
bring the three down CU there's not two
in that column and then if you multiply
this 4 8 it's 16 now many of you could
have just said okay I know the common uh
greatest common factor of the
coefficients is 16 but I wanted to show
how you can find that now but we aren't
finished okay so let's write 16 and then
what we do is we find for com we look
for common variables we have a and a
that's common and then we take the
smallest exponent and that is
four so now we have the greatest common
factor of these two now what we do is we
divide okay so I'm going to so it's not
confusing looking 48 a 7th / 16 a 4
minus 16 a 4th / 16 a to 4th now when we
we divide let's go ahead and do this 16
goes
into um 483
* uh bring down the A and that will be 7
- 4 so that's a 3r minus 16 / 16 is 1
and then these cancel okay so now we
need to go back so we've gotten the G
the greatest common factor we have
divided now we need to leave with the co
with the greatest common factor and that
is
16 a to
4th so there it is factored I'll
Circle okay so the factored 48 a 7th -
16 a 4th factor is this okay let's work
another
example okay remember we're going to use
g d L greatest common factor divide lead
with the greatest common factor so now
we need to find the greatest common
factor of these two monomials okay so uh
let's get started I know many of you can
probably glance and see that the
greatest common factor is nine but I'm
going to create a factor tree just so
you know how I found that okay so here's
the factor tree of 9 3 and three and a
54 prime numbers I'll Circle them and
then what I've done is I've written them
in this box and remember the rule is
that if you have to have two in a column
to bring the number down so we have
three and three so that
equals nine now uh we need to go over
here and we need
to um find the variables so we have nine
and so we have an X and an
X and the lowest um expon onent is one
and then we have a y and a y and the
lowest exponent is three so here is the
greatest common factor so we have this
portion done now let's divide we have 9
x^2 y 4 / 9 x y 3r +
54x y cubed over 9 x y I CU so when we
divide 9 / 9 is 1 uh X um bring down the
x 2 - 1 is 1 and then with the Y 4 - 3
is 1
plus 9 goes into 54 6 times uh the X's
cancel the Y's cancel okay so let's put
this in parenthesis remember you don't
have to have the one in front of it now
remember we can't forget we've got to
lead we've got this done we've got to
lead with our um greatest common factor
so that is
9x y Cub so here is it factored this
binomial factored becomes this thanks
for watching and remember kindness
multiplies kindness be kind to someone
today
