December 30, 2022

Distance Between Two Points - Formula, Derivation, Examples

The theory of distance is crucial in both math and daily life. From straightforward calculating the length of a line to designing the quickest route among two points, understanding the length among two points is important.


In this blog, we will inspect the formula for distance within two points, go through some examples, and talk about realistic applications of this formula.

The Formula for Distance Within Two Points

The distance within two points, often signified as d, is the extent of the line segment linking the two points.


Mathematically, this can be represented by drawing a right triangle and utilizing the Pythagorean theorem. Per the Pythagorean theorem, the square of the distance of the longest side (the hypotenuse) is equivalent to the sum of the squares of the lengths of the two other sides.


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


In instance of finding the distance between two locations, we can represent the points as coordinates on a coordinate plane. Let's assume we have point A with coordinates (x1, y1) and point B at (x2, y2).


We could further employ the Pythagorean theorem to acquire the following formula for distance:

d = √((x2 - x1)2 + (y2 - y1)2)


In this formula, (x2 - x1) represents the length on the x-axis, and (y2 - y1) portrays the length along y-axis, forming a right angle. By taking the square root of the sum of their squares, we obtain the distance among the two extremities.


Here is a visual illustration:


Instances of Utilizations of the Distance Formula

Considering we possess the formula for distance, let's look at few instances of how it can be used.

Working out the Length Among the Two Points on a Coordinate Plane

Assume we have two points on a coordinate plane, A with coordinates (3, 4) and B with coordinates (6, 8). We will employ the distance formula to find the length 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 length within points A and B is 5 units.

Calculating the Distance Within Two Locations on a Map

In addition to working out the distances on a coordinate plane, we could also use the distance formula to calculate distances within two points on a map. For example, assume we posses a map of a city along a scale of 1 inch = 10 miles.


To figure out the distance within two points on the map, such as the city hall and the airport, we could easily calculate the distance within the two points employing a ruler and convert the measurement to miles using the map's scale.


When we measure the length within these two points on the map, we figure out it is 2 inches. We convert this to miles using the map's scale and find out that the actual distance among the city hall and the airport is 20 miles.

Working out the Length Between Two Locations in Three-Dimensional Space

In addition to calculating lengths in two dimensions, we can also utilize the distance formula to work out the distance among two points in a three-dimensional space. For instance, suppose we possess two locations, A and B, in a three-dimensional space, with coordinates (x1, y1, z1) and (x2, y2, z2), individually.


We will use the distance formula to find the distance between these two points as follows:

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


Using this formula, we can determine the length among any two points in three-dimensional space. For instance, if we possess two locations A and B with coordinates (1, 2, 3) and (4, 5, 6), individually, we could figure out the length within 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 length between points A and B is roughly 3.16 units.

Utilizations of the Distance Formula

Now that we have seen some instances of utilizing the distance formula, let's examine some of its uses in mathematics and other areas.

Measuring Distances in Geometry

In geometry, the distance formula is used to calculate 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 figure out the distances of the sides AB, BC, and AC. These distances can be employed to calculate other characteristics of the triangle, for example its interior angles, area, perimeter.

Solving Problems in Physics

The distance formula is further used in physics to work out questions involving speed, distance and acceleration. For example, if we perceive the first location and velocity of an object, in addition to the time it requires for the object to transport a certain length, we could utilize the distance formula to work out the object's final location and speed.

Analyzing Data in Statistics

In statistics, the distance formula is often used to figure out the length between 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 represent high-dimensional data in a lower-dimensional space.

Go the Distance with Grade Potential

The distance formula is ac crucial concept in mathematics that enables us to calculate the length within two points on a plane or in a three-dimensional space. By using the Pythagorean theorem, we can extract 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 utilizations are important for anyone fascinated in math and its uses in other areas. If you're struggling regarding the distance formula or any other mathematical concept, reach out to Grade Potential tutoring for customized help. Our experienced tutors will help you master any mathematics topic, from algebra to calculus and beyond.


Call us today to know more and schedule your first tutoring session.