The function g(x) = 5x2 – 10x written in vertex form is g(x) = 5(x – 1)2 – 5. The function g(x) is shown on the graph along with the parent function, f(x) = x2. Which statement is true concerning the vertex and the axis of symmetry of g(x)?
The general vertex form of the a quadratic function is y = (x - h)^2 + k.
In this form, the vertex is (h,k) and the axis of symmetry is x = h.
Then, you only need to compare the vertex form of g(x) with the general vertex form of the parabole to conclude the vertex point and the axis of symmetry.
g(x) = 5(x-1)^2 - 5 => h = 1 and k = - 5 => theis vertex = (1, -5), and the axis of symmetry is the straight line x = 1.
Answer: the vertex is (1,-5) and the symmetry axis is x = 1.
