Question

What is the y-coordinate of the vertex?
Y=2(x-3)( x-9)

Answer 1

-18

Explanation:

First, to find the y coordinate of the vertex, we need to find the x coordinate of the vertex.

The vertex will always be in the middle of the roots of the quadratic. The roots of the polynomial are 3 and 9, so the x coordinate of the vertex will be (3+9)/2 = 6.

Now that we know the x coordinate of the vertex, we can just plug in 6 for x to find the y coordinate:

2(6-3)(6-9)

=2(3)(-3)

=-18