What is the axis of symmetry and vertex for the graph #f(x) = 3 + 2x – x^2#?

1 Answer
May 12, 2016

axis of symmetry is #x = 1#
Vertex is at #(1,4)#

Explanation:

This is an example of a parabola. It has the standard form:
#f(x) = y = ax^2 + bx + c#
In #f(x) = -x^2 + 2x + 3" "# a = -1, b = 2, c = 3.

The formula to find the axis of symmetry is: #x = (-b)/(2a)#

#x = (-2)/(2(1)) = 1#

The vertex lies on the axis of symmetry, if #x = 1#

#y = -(1) + 2(1) + 3 = 4#

Vertex is at (1,4)