Answer:
The vertex is at (1, -108).
Step-by-step explanation:
We have the function:
[tex]f(x)=3(x-7)(x+5)[/tex]
And we want to find its vertex point.
Note that this is in factored form. Hence, our roots/zeros are x = 7 and x = -5.
Since a parabola is symmetric along its vertex, the x-coordinate of the vertex is halfway between the two zeros. Hence:
[tex]\displaystyle x=\frac{7+(-5)}{2}=\frac{2}{2}=1[/tex]
To find the y-coordinate, substitute this back into the function. Hence:
[tex]f(1)=3((1)-7)((1)+5)=3(-6)(6)=-108[/tex]
Therefore, our vertex is at (1, -108).
