### Home > CAAC > Chapter 8 > Lesson 8.2.3 > Problem 8-68

8-68.

The roots (

*x*-intercepts) of*y*= 2*x*^{2}− 16*x*+ 30 are (3, 0) and (5, 0). Homework Help ✎What is the

*x*-coordinate of the vertex? How do you know?Use your answer to part (a) above to find the

*y*-coordinate of the vertex. Then write the vertex as a point (*x*,*y*).

The *x* coordinate of the vertex is halfway between 3 and 5.

*x* = 4

Substitute the vertex value of *x* back into the original equation to find *y*.

*y* = 2(4^{2}) − 16(4) + 30

Solve for *y*.

*y* = −2

Coordinates = (4, −2)