00:01
Before you factor, you want to set this equation equal to zero.
00:04
So we're going to subtract 12x from both sides.
00:10
So we're left with 4x squared.
00:12
And because there's only an x here, it's going to be minus 12x and then plus 9 because there's no like terms, now equal to x.
00:21
Now you need to multiply your a and your c together, so that will make 4 times 9 makes 36.
00:29
Now you need to figure out what two numbers you multiply to get positive 36, but when you add those two numbers, you get negative 12.
00:38
So i know that negative 6 times negative 6 will give you positive 36.
00:46
And when we add these two together, it will give me negative 12.
00:51
So we will be using negative 6 and negative 6.
00:56
So when we factor it, okay? what you want to do is factor the 4x squared first because we know that the outside needs to make negative 6 and the inside needs to make negative 6.
01:11
But we know that something times something needs to make 4x squared.
01:16
So what can make 4? what are the numbers that can make 4? you can do 4 times 1, but if you do 4, 4 times something, does not make negative 6.
01:29
So we're not going to use 1 and 4.
01:31
What's another way to make 4? there's 2 times 2...