00:03
We're going to convert this quadratic from general form to standard form.
00:08
So to do that, we're going to want to factor out the negative one so that x squared has positive one as a coefficient.
00:18
And we're going to leave room for that special term.
00:22
There's our constant.
00:24
And if we're going to add it, we have to subtract the special term as well.
00:28
So don't forget that negative one we factored out.
00:32
All right.
00:32
So what is it that we're going to add? we're going to take whatever the x coefficient is, which is three.
00:38
Over two and then we're going to square it.
00:40
So three halves squared.
00:46
Do it on both here.
00:48
Three halves squared.
00:51
So now we have a perfect square binomial.
00:55
Hey, minus one times.
00:59
All right, and the binomial is x.
01:01
That's from here.
01:03
This sign is positive.
01:04
So this sign is positive.
01:06
And then whatever this is, the thing being squared is what goes here.
01:11
Now we just have to figure out with the constant.
01:14
Is.
01:14
So, 3 over 2 squared is 9 4ths.
01:19
We have negative 1 times that would make it negative, but this other negative would make it positive.
01:23
So we have 3 plus 9 4s, and 3 is the same thing as 12 4ths.
01:29
So really our constant is 9 plus 12 is 21, so plus 21 over 4, which is 5 in a quarter.
01:38
So that is our standard form.
01:45
And from here, the graph won't, be too hard to do.
01:48
We have our vertex we can find from this is the x coordinate.
01:53
All we have to do is multiply by negative one, negative three halves.
01:57
And this here is the y coordinate, positive 21 over 4.
02:04
So 21 over 4 is 5 and a quarter.
02:06
Three halves is one and a half.
02:08
So negative 1 and a half and 5 and a quarter.
02:11
We're going to have to guesstimate, but i think we'll do all right.
02:15
Another easy point is always the y intercept.
02:18
That's when x is zero, which means we have negative zero minus zero plus three.
02:24
So when x is zero, y is three.
02:27
Because parabolas are symmetric about the vertex, if we're one and a half to the right and we get the value of three, then one and a half to the left will also have a value of three.
02:40
And we're going to go for our x intercept as well...