00:01
All right, so for this problem here, we're trying to factor this expression.
00:05
The first step is to notice that we can take out a y -squared from this whole thing, because each of these terms is divisible by y -squared.
00:14
So we can take y -squared all the way out, and then we're left in the parentheses with y -squared plus 5 -y -minus 84.
00:25
And the next step is to factor this polynomial here by checking for a common factor.
00:32
We're going to take the first coefficient and multiply by the last.
00:36
So 1 times negative 84 is 84.
00:41
And so we're looking for two numbers that multiply to negative 84, but add to positive 5, because positive 5 is our middle term.
00:48
And so two numbers that do this for us are 12 and negative 7, have a product of negative 84 and a sum of 5.
00:55
So now we're going to expand this expression by expanding the middle term.
01:02
So minus 7y plus 12y minus 84...