Question

If a quadratic function has zeroes at x = -8 and x = 10, what is the x-coordinate of the vertex?​

Answer 1

I think that that person is right

Answer 2

To find the x intercepts you must put y=0; in this way you fix at zero the coordinate y of the points you are seeking. You are left with finding the coordinate x of the points. If y=0 you are left with: 0=ax2+bx+c which is a second degree equation.

Explanation: