Equivalent quadratic expressions
Vertex paths

Use the dynamic figures below to follow the path that the vertex of a quadratic function makes as you change one or more of the parameters that define the function.

Use the figure below, as well as the Product Form, Polynomial Form, and Vertex Form tools, to investigate various paths that are formed by the vertex when you change one or more parameters.
  • Make conjectures about the shapes of the paths formed and check them by graphing a function g (use the input box in the lower part of the tool) that describes the path.
  • Use algebraic expressions to explain, generalize, and prove phenomena you have noticed.


  • f(x)=m(x-r)(x-s)
    change
    trace
    m=
    r=
    s=
    f(x)=ax2+bx+c
    change
    trace
    a=
    b=
    c=





    Vertex Form
    Polynomial Form
    Product Form

    Reading information about a function
    Immunization against the common cold
    Numeric surprises
    Constructing functions
    Wage increase
    Partial pictures
    Examining value tables
    Families of functions
    Vertex paths
    Family and sub-families
    Parametric families

    Exercise 1
    Exercise 2
    Exercise 3
    Exercise 4
    Exercise 5
    Exercise 6
    Exercise 7
    Exercise 8
    Exercise 9
    Exercise 10
    Exercise 11
    Exercise 12