March 16, 2023

Equation, Properties, Examples | Parabola Formula

The parabola is a fascinating and multifaceted geometric shape that managed to drew the attention of mathematicians and scientists for hundreds of years. Its unusual properties and unsophisticated yet elegant equation makes it a strong tool for molding a broad assortment of real-world phenomena. From the trajectory of a projectile to the shape of a satellite dish, the parabola performs a crucial role in various domains, involving engineering, physics, architecture, and math.

A parabola is a type of conic section, that is a curve created by overlapping a cone through a plane. The parabola is determined with a quadratic equation, and its characteristics, for example the focus, directrix, vertex, and symmetry, offer precious insights into its performance and uses. By understanding the parabola formula and its properties, we could gain a deeper appreciation for this rudimental geometric shape and its multiple applications.

In this article, we wish to examine the parabola in detail, from its equation and properties to instances of in what way it can be used in many domains. Even if you're a learner, a professional, or just interested regarding the parabola, this article will provide a comprehensive overview of this interesting and crucial concept.

Parabola Equation

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

y = ax^2 + bx + c

here a, b, and c are constants which establish the size, shape, and position of the parabola. The value of a decides whether the parabola opens up or down. If a > 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 location where the curve shifts direction. It is also the point where the axis of symmetry intercepts the parabola. The axis of symmetry is a line that passes across the vertex and divides the parabola into two symmetrical halves.


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


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


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


The parabola crosses the x-axis at two points, provided by the formula:

x = (-b ± sqrt(b^2 - 4ac)) / 2a

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

Examples of Parabolas

Here are few simple examples of Parabolas:

Example 1: Graphing a Parabola

Let's graph the parabola y = x^2 - 4x + 3. First, we have to find the vertex, axis of symmetry, and intercepts. We can utilize the formula:

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

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

vertex = (2, -1)

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

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

x^2 - 4x + 3 = 0

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

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

In the end, the y-intercept is the point (0, c) = (0, 3).

Utilizing this information, we can plot the graph of the parabola by plotting the vertex, the x-intercepts, and the y-intercept, and drawing the curve of the parabola between them.

Example 2: Application of Parabola in Physics

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

y = xtan(θ) - (gx^2) / (2v^2cos^2(θ))

here g is the acceleration because of gravity, and x and y are the horizontal and vertical length covered by the projectile, respectively.

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


In conclusion, the parabola formula and its properties perform an essential role in several domains of study, including mathematics, architecture, physics, and engineering. By knowing the equation of a parabola, its characteristics such as the directrix, vertex, and focus, and symmetry, and its several uses, we can obtain a deeper comprehension of how parabolas work and how they could be used to model real-world phenomena.

Whether you're a learner struggling to comprehend the concepts of the parabola or a professional looking to use parabolic equations to real-world problems, it's important to possess a solid groundwork in this fundamental topic.

That's where Grade Potential Tutoring enters. Our adept instructors are accessible online or face-to-face to offer personalized and productive tutoring services to guide you master the parabola and other mathematical theories. Contact us today to plan a tutoring session and take your arithmetic abilities to the next stage.