The Vertex Form: the Quadratic Equation Form

The Vertex Form: the Quadratic Equation Form

Before getting into the details of vertex form, let initiate with its standard quadratic equation. As we know that the quadratic relation is a relation that has an equation in the following form y=ax2+bx+c where (a), (b), and (c) are real numbers and (a) not equal to zero. Thus, in a quadratic equation, you can expect a linear graph to look like a “u” shape either in upward form or in upside downward form. In other words, you can refer to its relation as a parabola depending on the exact equation pointing upward direction or in a downward. Thus, you can find either be a broader or narrower “U” shape. It, of course, does not need to have it start at its origin as it can begin at any point in the linear graph.

Introduction to Vertex Form: Another Quadratic Equation

Vertex form is one of a quadratic equation that you can write in like this


where(a), (h), and (k) are its numbers. “a” is the constant in the vertex form. It’s important to note that you can write a quadratic equation in different ways other than the vertex form, such as Standard Form [y=ax2+bx+c] and Factored Form [y=a(x-r)(x-s)].

We will get around to those forms later on but for now, let’s pay special attention to this very useful vertex form [f(x)=a(x-h)2+k]. The beauty of vertex form already hints to us through its name. In this form, it is effortless for us to identify the Vertex. The Vertex is (h,k). So, let’s put the number into this to try an example.

What would be the Vertex be here: y=3(x-2)2 +1 for the given equation?

Well, if you reference thisy=a(x-h)2+k; Vertex: (h, k). We can see that it would be (h) and (k), which is Vertex: (2, 1) in this example but be careful not to say that Vertex is (negative 2) because the Vertex is actually (2,1). If you thought that (h) was equal to (negative 2), then you should try substituting (negative 2) into (H), and you’d find yourself getting [(x)-(-2)] which becomes the (x+2) that would ofcourse entirely different from what we’re looking for in the vertex form.

vertex form calculator
vertex form calculator

Vertex form Illustration

The Vertex is a point where two or more lines, curves, or edges coincide in geometry. According to this definition, the intersection of two lines forms an angle, and polygons and polyhedra have vertices at their corners.

For example, there are four corners of a square, and each corner is known as a vertex. Vertices are the plural class of the Vertex. Most commonly, the word vertex refers to the corners of a polygon.

Whenever two lines meet, they form an angle known as an included angle. Each polygon vertex consists of an angle that represents the polygon’s interior. Alternatively, the term vertex is sometimes used to describe the ‘top’ or high point, such as the ‘top’ corner of an isosceles triangle. It is opposite its base, although this is not its strict mathematical definition.

Illustration to Equation: Vertex Form

The vertex form of an equation can be used to write out the equation of a parabola.

It’s typical to find quadratic equations written as ax2+bx+c, which are graphed as parabolas. By setting the equation equal to zero (or using the quadratic formula), you can easily find the roots of the equation (where the parabola intersects the x-axis).

However, the standard quadratic form is less proper if you need to find a parabola’s Vertex. Therefore, your quadratic equation should be converted to vertex form instead.

You can write a quadratic function in three different ways. The standard form of a quadratic was discussed in the previous lesson. The vertex form of a quadratic will be discussed in this lesson. There are two types of vertex forms:

y = a(x-h)2 + k

Vertex form graphs have the following properties:

  • If a is positive, the graph opens upward, and if ais negative, it extends downward
  • If “h” is positive, the graph shifts right if his negative, the graph shifts left.
  • The chart shifts up if “k” is positive;the graph shifts down if k is negative.
  • The symmetry axis equals the line x = h, and the Vertex is the point ( h, k).

Optimization Problems

In optimization problems, quadratic functions often appear when we need to determine the extreme value of the function of vertex form or the vertex coordinates.

You can find the dimensions of a rectangle, for example, by finding the x-coordinate of the Vertex of a quadratic equation when a given perimeter and largest area are known.

Optimization is the process of finding a function whose extreme values are determined by imposing a given constraint on it.

Let’s practice this technique by solving the following problem.

For a rectangular field with a 200-yard length that needs to be fenced on three sides (there is an existing wall on the fourth side), we will determine the dimensions of the rectangular field.

The following steps to vertex form will help you determine the dimensions.

  • Express the field side parallel to (x) surface and another surface side with (y). For example, take a function of the area field in (x) and (y).
  • Implement an expression for the constraint.
  • Derive the function achieved in 1. in terms of a particular variable, using the constraint in 2.
  • Provide the x– coordinate of the vertex corresponding to the quadratic function from 3.


What is the Vertex Formula?

The Vertex formula is used to find the coordinates of the point where the parabola crosses its axis of symmetry. The coordinates are given as (h,k). Thus, the Vertex of a parabola is a location where the parabola is at minimum when it starts upward or at maximum when it’s open downward. Thus, the parabola shifts (or) alters its direction.

What is the Formula for Finding the Vertex on X Coordinates?

Focusing on the standard form of a parabola y = ax2 + bx + c and the vertex equation y = a(x – h)2 + k, we can get the first formula of vertex i.e.

The vertex formula will be: (h, k) = (-b/2a, -D/4a) where D = b2 – 4ac

How do you Use Vertex Formula?

Parabola equation can let you calculate the vextex of any parabola in the graph. The parabola equation for vertex form is: y = ax2 + bx + c. Where [h=(-b/2a)] and [k=(-D/4a) in the given form of D = b2 – 4ac.

Leave a Reply

Your email address will not be published. Required fields are marked *