March 16, 2023

Equation, Properties, Examples | Parabola Formula

The parabola is a fascinating and multifaceted geometric shape that has captured the attention of mathematicians and scientists for centuries. Its unique properties and simple yet exquisite equation makes it a strong tool for shaping a wide assortment of real-life phenomena. From the trajectory of a projectile to the shape of a satellite dish, the parabola plays a crucial role in many fields, including physics, architecture, engineering, and math.

A parabola is a type of conic portion, which is a curve created by intersecting a cone over a plane. The parabola is specified with a quadratic equation, and its features, such as the vertex, focus, directrix, and symmetry, give valuable understanding into its action and applications. By comprehending the parabola formula and its features, we can get a detailed appreciation for this essential geometric shape and its multiple usages.

In this article, we will study the parabola in detail, from its equation and properties to examples of how it can be applied in various domains. Even if you're a learner, a professional, or simply curious regarding the parabola, this blog will offer a complete overview of this fascinating and essential concept.

Parabola Equation

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

y = ax^2 + bx + c

at this point a, b, and c are constants that decide the shape, size, and position of the parabola. The value of a decides if the parabola opens up or down. If a > 0, the parabola opens upward, and if a less than 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 spot where the curve changes direction. It is additionally the point where the axis of symmetry intercepts the parabola. The axis of symmetry is a line which passes across the vertex and divides the parabola into two proportionate portions.


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


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


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


The parabola crosses 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 point (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 figure out the vertex, axis of symmetry, and intercepts. We can apply the formula:

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

to figure out the vertex. Placing 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.

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

x^2 - 4x + 3 = 0

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

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

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

Using this information, we can sketch the graph of the parabola by plotting the vertex, the x-intercepts, and the y-intercept, and drawing 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 applications of the parabola in physics. While a projectile is launched or thrown into the air, it follows a path that is described by 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 due to gravity, and x and y are the horizontal and vertical length traveled by the object, respectively.

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


In conclusion, the parabola formula and its properties play an important function in many domains of study, including math, physics, engineering, and architecture. By understanding the equation of a parabola, its properties for example the focus, directrix, and vertex, and symmetry, and its various applications, we could obtain a deeper understanding of how parabolas function and how they could be utilized to model real-world scenario.

Whether you're a student struggling to grasp the theories of the parabola or a professional want to use parabolic equations to real-world challenges, it's essential to possess a solid groundwork in this fundamental topic.

This's where Grade Potential Tutoring enters. Our adept instructors are available online or face-to-face to provide customized and effective tutoring services to help you conquer the parabola and other math concepts. Contact us today to plan a tutoring session and take your mathematical abilities to the next stage.