Respuesta :
Answer:
The vertex of the function is (h,k)=(3,3)
The axis of symmetry is x=3.
Step-by-step explanation:
Given : Function [tex]y=2x^2-12x+21[/tex]
To find : Determine the axis of symmetry and the vertex of the given function.
Solution :
The quadratic function is in the form, [tex]y=ax^2+bx+c[/tex]
On comparing, a=2 , b=-12 and c=21
The vertex of the graph is denote by (h,k) and the formula to find the vertex is
For h, The x-coordinate of the vertex is given by,
[tex]h=-\frac{b}{2a}[/tex]
[tex]h=-\frac{-12}{2(2)}[/tex]
[tex]h=\frac{12}{4}[/tex]
[tex]h=3[/tex]
For k, The y-coordinate of the vertex is given by,
[tex]k=f(h)[/tex]
[tex]k=2h^2-12h+21[/tex]
[tex]k=2(3)^2-12(3)+21[/tex]
[tex]k=18-36+21[/tex]
[tex]k=3[/tex]
The vertex of the function is (h,k)=(3,3)
The x-coordinate of the vertex i.e. [tex]x=-\frac{b}{2a}[/tex] is the axis of symmetry,
So, [tex]x=-\frac{b}{2a}=3[/tex] (solved above)
So, The axis of symmetry is x=3.
