00:01
All right, this problem asks us to factor 6m squared minus 15m.
00:08
So i set up a strategy that i showed in my previous example, which is called double division, since i'm dividing two terms at the same time.
00:18
Common factors are what go on the outside of the division.
00:22
You cannot put something on the outside that is not able to multiply wholly to get one of these two terms.
00:31
And our goal is to find the greatest common factor, and then to rewrite this expression with the greatest common factor multiplied by the difference of the two remaining terms.
00:45
And so we'll take a look at how this problem not only helps us with finding the greatest common factor, but then writing it in this expression.
00:52
So i'm going to begin by thinking of what makes these numbers.
00:56
6 is made with 2 and 3, 15 is made with 3 and 5, and so the number that i said in both, the common factor is three.
01:07
So i'll put three here.
01:09
Three times something gives me six, and that something is a two.
01:14
And so on the bottom is the answer to the double division.
01:18
Three goes into six two times.
01:20
Three goes into 15, five times.
01:24
Next i look at the variable.
01:26
I have this variable, m to the power of two, which is the same thing as m times m.
01:32
And then here i have one factor of m.
01:35
So they both have a factor of m.
01:37
I'll bring that out.
01:38
But i can't bring out m squared because this, the 15m term, does not have a second power or a second factor of m.
01:52
Since i took the m out with this division, there is no longer any m's in my second term.
01:58
But in my first term, it was m times m.
02:01
So by removing one of the m's through division, there is one m still there.
02:06
And whatever operation was between the terms here is between the terms again.
02:11
Now i'm going to look at these terms and see if they share anything that i missed...