Graphing a Quadratic Function First graph vertex Find a point
Draw axis of symmetry through vertex Reflect point over axis Graphing a Quadratic Function
Finding a Quadratic Model Create a scattergram Select a vertex (Doesn’t have to be data point) Select non-vertex point Plug vertex in for h and k, and the nonvertex point for x and f(x)/y into a standard equation Solve for a Then substitute a into the standard equation
Quadratic in Standard Form Find y-intercept (0, c) Find symmetric point Use midpoint formula of the x-coordinates of the symmetric points to find the x- coordinate of the vertex Plug x-coordinate of the vertex into equation for x
Graphing Quadratics Y-intercept –(0, 7) Symmetry Point
Maximum/Minimum For a quadratic function with vertex (h, k) If a > 0, then the parabola opens upward and the vertex is the minimum point (k minimum value) If a < 0, then the parabola opens downward and vertex is the maximum point (k maximum value)
Maximum Value Model A person plans to use 200 feet of fencing and a side of her house to enclose a rectangular garden. What dimensions of the rectangle would give the maximum area? What is the area?