March 16, 2023

Equation, Properties, Examples | Parabola Formula

The parabola is a fascinating and versatile geometric shape that managed to captured the attention of mathematicians and scientists for ages. Its unique properties and plain yet elegant equation makes it a strong tool for modeling a wide array of real-life phenomena. From the flight path of a projectile to the shape of a satellite dish, the parabola performs a crucial role in many fields, including engineering, physics, architecture, and mathematics.

A parabola is a kind of U-shaped piece, that is a curve formed by intersecting a cone over a plane. The parabola is defined by a quadratic equation, and its characteristics, for instance the vertex, focus, directrix, and symmetry, provide precious insights into its performance and applications. By grasping the parabola formula and its properties, we could gain a deeper recognition for this fundamental geometric shape and its many uses.

In this blog article, we wish to explore the parabola in depth, from its equation and properties to instances of in what way it can be used in various fields. Even if you're a student, a working professional, or simply interested regarding the parabola, this article will provide a complete overview of this fascinating and crucial idea.

Parabola Equation

The parabola is stated with a quadratic equation of the form:

y = ax^2 + bx + c

where a, b, and c are constants that determine the shape, size, and position of the parabola. The value of a controls if the parabola opens up or down. If a is greater than 0, the parabola opens upward, and if a < 0, the parabola opens downward. The vertex of the parabola is located at the point (-b/2a, c - b^2/4a).

Properties of the Parabola

Here are the properties of Parabola:


The vertex of the parabola is the point where the curve switches direction. It is further the point where the axis of symmetry crosses the parabola. The axis of symmetry is a line which moves through the vertex and splits the parabola within two symmetrical halves.


The focus of the parabola is the point] on the axis of symmetry that is equidistant from the vertex and the directrix. The directrix is a line that is perpendicular to the axis of symmetry and located at a distance of 1/4a units from the vertex.


The directrix is a line which is perpendicular to the axis of symmetry and located at a distance of 1/4a units from the vertex. All points on the parabola are equal distance from the directrix and the focus.


The parabola is symmetric with respect to its axis of symmetry. Which defines that if we consider any location on one side of the axis of symmetry throughout the axis, we get a corresponding point on the other side of the axis.


The parabola intersects the x-axis at two points, given by the formula:

x = (-b ± sqrt(b^2 - 4ac)) / 2a

The parabola intersects the y-axis at the location (0, c).

Examples of Parabolas

Here are some simple examples of Parabolas:

Example 1: Graphing a Parabola

Let's graph the parabola y = x^2 - 4x + 3. Primarily, we are required to calculate the vertex, axis of symmetry, and intercepts. We can use the formula:

vertex = (-b/2a, c - b^2/4a)

to find the vertex. Plugging in the values a = 1, b = -4, and c = 3, we obtain:

vertex = (2, -1)

So the vertex is located at the point (2, -1). The axis of symmetry is the line x = 2.

Subsequently, we can figure out the x-intercepts by taking y = 0 and calculating for x. We get:

x^2 - 4x + 3 = 0

(x - 3)(x - 1) = 0

Accordingly the parabola intersects the x-axis at x = 1 and x = 3.

Finally, the y-intercept is the coordinates (0, c) = (0, 3).

Using this knowledge, we can draw the graph of the parabola through plotting the vertex, the x-intercepts, and the y-intercept, and portraying the curve of the parabola within them.

Example 2: Application of Parabola in Physics

The parabolic curve of a projectile's trajectory is a standard example of the parabola in physics. When an object is launched or thrown into the air, it follows a course which is represented by a parabolic equation. The equation for the course of a projectile launched from the ground at an angle θ through an initial velocity v is provided by:

y = xtan(θ) - (gx^2) / (2v^2cos^2(θ))

here g is the acceleration as a result of gravity, and x and y are the horizontal and vertical distances covered by the object, respectively.

The trajectory of the projectile is a parabolic curve, with the vertex at the location (0, 0) and the axis of symmetry corresponding to the ground. The focus of the parabola portrays the landing spot of the projectile, and the directrix represents the height above the ground where the projectile would hit if it weren’t affected by gravity.


In conclusion, the parabola formula and its properties play an important role in several domains of study, including math, architecture, physics, and engineering. By knowing the equation of a parabola, its characteristics for example the focus, directrix, and vertex, and symmetry, and its several applications, we can gain a detailed understanding of how parabolas work and how they could be utilized to model real-life phenomena.

Whether you're a learner struggling to comprehend the concepts of the parabola or a working professional want to use parabolic equations to real-life challenges, it's important to possess a strong foundation in this basic topic.

That's where Grade Potential Tutoring walks in. Our expert teachers are available online or face-to-face to offer customized and productive tutoring services to guide you master the parabola and other mathematical theories. Contact us today to schedule a tutoring session and take your math abilities to the next stage.