What is the axis of symmetry and vertex for the graph #y = 2x^2 - 4x + 1#?

1 Answer
Oct 4, 2016

The axis of symmetry is the line #x = 1#, and the vertex is the point (1, -1).

Explanation:

The standard form of a quadratic function is #y = ax^2 + bx + c#. The formula for finding the equation of the axis of symmetry is #x = (-b)/(2a)#. The x-coordinate of the vertex is also #(-b)/(2a)#, and the y-coordinate of the vertex is given by substituting the x-coordinate of the vertex into the original function.

For #y = 2x^2 - 4x +1#, #a = 2#, #b = -4#, and #c = 1#.

The axis of symmetry is:
#x = (-1*-4)/(2*2)#
#x = 4/4#
#x = 1#

The x-coordinate of the vertex is also 1. The y-coordinate of the vertex is found by:
#y = 2(1)^2 - 4(1) + 1#
#y = 2(1) - 4 + 1#
#y = 2 -3#
#y = -1#
So, the vertex is the point (1, -1).