December 30, 2022

Distance Between Two Points - Formula, Derivation, Examples

The idea of length is crucial in both math and routine life. From straightforward calculating the length of a line to designing the shortest route between two locations, understanding the length within two points is important.


In this article, we will explore the formula for distance between two extremities, review a few examples, and talk about realistic utilizations of this formula.

The Formula for Distance Within Two Points

The distance between two points, often denoted as d, is the length of the line segment linking the two points.


Mathematically, this can be portrayed by drawing a right triangle and utilizing the Pythagorean theorem. According to Pythagorean theorem, the square of the distance of the extensive side (the hypotenuse) is equivalent to the sum of the squares of the distances of the two other sides.


The formula for the Pythagorean theorem is a2 + b2 = c2. As a consequence, √c2 will equal the distance, d.


In the case of finding the distance within two points, we can depict the extremities as coordinates on a coordinate plane. Let's say we possess point A with coordinates (x1, y1) and point B at (x2, y2).


We could thereafter utilize the Pythagorean theorem to acquire the following formula for distance:

d = √((x2 - x1)2 + (y2 - y1)2)


In this formula, (x2 - x1) depicts the distance on the x-axis, and (y2 - y1) depicts the distance along y-axis, constructing a right angle. By considering the square root of the sum of their squares, we get the distance within the two extremities.


Here is a graphical illustration:


Examples of Applications of the Distance Formula

Once we have the formula for distance, let's look at few examples of how it can be used.

Working out the Length Between Two Points on a Coordinate Plane

Assume we have two locations on a coordinate plane, A with coordinates (3, 4) and B with coordinates (6, 8). We will use the distance formula to figure out the distance within these two locations as ensues:


d = √((6 - 3)2+ (8 - 4)2)

d = √(32 + 42)

d = √(9 + 16)

d = √(25)

d = 5


Therefore, the distance within points A and B is 5 units.

Calculating the Distance Within Two Extremities on a Map

In addition to figuring out the distances on a coordinate plane, we can further use the distance formula to calculate lengths within two locations on a map. For instance, assume we posses a map of a city with a scale of 1 inch = 10 miles.


To figure out the length among two locations on the map, similar to the airport and the city hall, we could simply calculate the distance among the two locations using a ruler and change the measurement to miles utilizing the map's scale.


When we calculate the distance among these two locations on the map, we work out it is 2 inches. We convert this to miles using the map's scale and find that the true distance between the city hall and the airport is 20 miles.

Working out the Distance Between Two Points in Three-Dimensional Space

In addition to finding lengths in two dimensions, we could further use the distance formula to calculate the distance between two locations in a three-dimensional space. For instance, assume we possess two locations, A and B, in a three-dimensional space, with coordinates (x1, y1, z1) and (x2, y2, z2), respectively.


We will employ the distance formula to work out the distance within these two locations as ensuing:

d = √((x2 - x1)2 + (y2 - y1)2 + (z2 - z1)2)


Utilizing this formula, we can identify the length among any two points in three-dimensional space. For instance, if we have two points A and B with coordinates (1, 2, 3) and (4, 5, 6), individually, we can find the length between them as ensues:


d = √((4 - 1)2 + (5 - 2)2 + (6 - 3)2)

d = √(32 + 32 + 32)

d = √(9 + 9 + 9)

d = √(27)

d = 3.16227766


Therefore, the distance between points A and B is roughly 3.16 units.

Utilizations of the Distance Formula

Now once we have looked at some examples of utilizing the distance formula, let's explore few of its Utilizations in mathematics and other fields.

Measuring Distances in Geometry

In geometry, the distance formula is used to work out the length of line segments and the sides of triangles. For example, in a triangle with vertices at points A, B, and C, we utilize the distance formula to calculate the lengths of the sides AB, BC, and AC. These distances could be utilized to measure other properties of the triangle, for example its interior angles, area, perimeter.

Solving Problems in Physics

The distance formula is also utilized in physics to solve problems involving distance, speed, and acceleration. For instance, if we recognize the initial position and velocity of an object, as well as the time it takes for the object to transport a specific length, we could use the distance formula to calculate the object's ultimate position and speed.

Analyzing Data in Statistics

In statistics, the distance formula is usually used to workout the distances within data points in a dataset. This is useful for clustering algorithms, that group data points which are close to each other, and for dimensionality reduction techniques, this portrays high-dimensional data in a lower-dimensional space.

Go the Distance with Grade Potential

The distance formula is an essential concept in math which enables us to work out the distance within two location on a plane or in a three-dimensional space. By utilizing the Pythagorean theorem, we can derive the distance formula and implement it to a variety of situations, from calculating distances on a coordinate plane to analyzing data in statistics.


Comprehending the distance formula and its applications are important for anyone interested in math and its applications in other areas. If you're having difficulties regarding the distance formula or any other mathematical concept, connect with Grade Potential tutoring for tailored help. Our professional teachers will assist you conquer any mathematics topic, from algebra to calculus and furthermore.


Connect with us today to learn more and schedule your first tutoring session.