Standard Form of the Equation

Key Questions

  • I believe you mean standard form. Standard form has another name, vertex form.

    This is a duplicate question, please read the link below as it also has an example: How do I convert the equation f(x)=x^2+6x+5f(x)=x2+6x+5 to vertex form?

  • The directrix of the parabola is a straight line that, together with the focus (a point), is used in one of the most common definition of parabolas.
    In fact, a parabola can be defined as *the locus of points PP such that the distance to the focus FF equals the distance to the directrix dd.

    Image by Maurizio Giaffredo

    The directrix has the property of being always perpendicular to the axis of symmetry of the parabola.

  • Answer:

    See the explanation section.

    Explanation:

    The term "standard form" is perhaps overused in mathematics.

    The standard form for a quadratics function (as a polynomial function) is f(x)=ax^2+bx+cf(x)=ax2+bx+c.

    The standard for for the equation of a parabola (also called the vertex form) is like the standard form for other conic sections.

    For a parabola with vertex (h,k)(h,k) through the points (h+-1,k+a)(h±1,k+a),
    (that is, it opens up or down)
    the standard form is y = a(x-h)^2 + ky=a(xh)2+k

    (If the parabola opens sideways, it includes the points (h+a, k+-1)(h+a,k±1) and has form x = a(y-k)^2+hx=a(yk)2+h.)

Questions