Question #eef57

1 Answer
Sep 6, 2016

Use the formula #x = (-b)/(2a)# to find the x coordinate, then plug in x to find the y coordinate.

Explanation:

The vertex of a parabola in form #y = ax^2 +bx +c# can be found using the formula #x = (-b)/(2a)# for the #x# coordinate.

so a = -4, b = 16, and c = -15.

#x =( -16)/(2(-4)) = 2#

Plug in x = 2 to the original equation to find the y coordinate of the vertex.

#y = (-4)(2)^2 + 16(2) -15 = 1#

The vertex is then #(2,1)#.