Answer:
The vertex is at (-1, -16).
Step-by-step explanation:
We are given the quadratic equation:
[tex]y = (x-3)(x+5)[/tex]
And we want to find its vertex.
Recall that the x-coordinate of the vertex is also the axis of symmetry. Since a parabola is symmetric about the axis of symmetry, the axis of symmetry is halfway between the two roots.
From the equation, we can see that our two roots are x = 3 and x = -5.
Hence, the axis of symmetry or the x-coordinate of the vertex is:
[tex]\displaystyle x = \frac{(3) + (-5)}{2} = -1[/tex]
To find the y-coordinate of the vertex, evaluate the equation at x = -1:
[tex]\displaystyle \begin{aligned} y(-1) &= ((-1)-3)((-1)+5)\\ &= (-4)(4) \\&= -16\end{aligned}[/tex]
Hence, the vertex is at (-1, -16).
