00:01
Here we are given this quadratic function and we are looking to find the vertex.
00:06
So the vertex is a coordinate point, x, y point, and to find it, it uses the formula opposite of b over 2a.
00:18
So looking at this equation that we have, a is the number in front of x squared, so because there's nothing written there, a would just be 1.
00:28
B is the next number, including the sign, so negative 8.
00:34
And then c would be the last number, again including the sign, so negative 9.
00:39
So now, if i do opposite of b, because here it's negative 8, i'm going to change that to positive 8 over 2 times, and what's in front of here written, there's nothing, but we know that it's a 1...