The function is .
The standard form of quadratic function is .
Find the axis of symmetry:
\Formula for the equation of the axis of symmetry: .
The value of are substitute in the formula,
.
The equation for the axis of symmetry is .
Find the vertex:
\To find the vertex, use the value of equation for the axis of symmetry as the x - coordinate of the vertex.
\To find the y - coordinate, substitute the value of in the original equation,
.
The vertex point is .
Determine whether the function has maximum or minimum value:
\The value of (negative), so the graph of function opens downward and has a maximum value. The maximum value (y - coordinate of the vertex) is
.
Find the y-intercept:
\To find the y - intercept, the value of substitute in the original equation,
.
The y - intercept is .
The axis of symmetry divides the parabola into two equal parts. So if there is a point on one side, there is a corresponding point on the other side that is the same distance from the axis of symmetry and has the same y - value. Connect the points with a smooth curve.
\The graph of the function, is