Please explain to me how to do this algebra problem?

Question

What is the vertex for the parabola y = 2x^ 2 - 8x+15

Answer 1

By using the equation -b/2a you can get the x coordinate of the vertex and then plug that answer into the original equation to fond the y component.

y=ax^2-bx+c, -b/2a
y=2x^2-8x+15, -(-8)/(2*2)=2, plug 2 in for x and y=7. So vertex is at (2,7)

Answer 2

there is a formula, it will help you find the head of parabola! A(x,y)