December 30, 2022

Distance Between Two Points - Formula, Derivation, Examples

The theory of distance is crucial in both math and everyday life. From straightforward measuring the extent of a line to figuring out the shortest route among two points, comprehending the length within two points is important.


In this blog, we will inspect the formula for distance between two locations, go through a few examples, and discuss real-life utilizations of this formula.

The Formula for Distance Within Two Points

The length within two points, often signified as d, is the extent of the line segment connecting the two locations.


In math, this can be represented by drawing a right triangle and employing the Pythagorean theorem. Per the Pythagorean theorem, the square of the length of the extensive side (the hypotenuse) is equivalent to the total of the squares of the distances of the two other sides.


The formula for the Pythagorean theorem is a2 + b2 = c2. Consequently, √c2 will as same as the length, d.


In the circumstance of working out the distance within two points, we can represent the extremities as coordinates on a coordinate plane. Let's assume we possess point A with coordinates (x1, y1) and point B at (x2, y2).


We can then use the Pythagorean theorem to extract the ensuing formula for distance:

d = √((x2 - x1)2 + (y2 - y1)2)


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


Here is a graphical representation:


Instances of Using the Distance Formula

Considering we possess the formula for distance, let's check out some instances of how it can be used.

Working out the Distance Among the Two Locations on a Coordinate Plane

Imagine 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 find the length within these two locations as follows:


d = √((6 - 3)2+ (8 - 4)2)

d = √(32 + 42)

d = √(9 + 16)

d = √(25)

d = 5


Hence, the distance between points A and B is 5 units.

Calculating the Length Between Two Points on a Map

In addition to working out the length on a coordinate plane, we can further utilize the distance formula to work out lengths between two points on a map. For example, assume we posses a map of a city along a scale of 1 inch = 10 miles.


To find the distance between two locations on the map, such as the city hall and the airport, we can simply calculate the distance among the two points employing a ruler and convert the measurement to miles utilizing the map's scale.


Once we calculate the distance between these two locations on the map, we work out it is 2 inches. We change this to miles using the map's scale and find that the true distance between the airport and the city hall 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 utilize the distance formula to figure out the distance between two points 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), individually.


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

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


Using this formula, we could identify the length between any two locations in three-dimensional space. For example, if we have two points A and B with coordinates (1, 2, 3) and (4, 5, 6), respectively, we could work out the length among 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


Hence, the distance between points A and B is just about 3.16 units.

Utilizations of the Distance Formula

Now that we have seen some examples of utilizing the distance formula, let's explore some of its applications in mathematics and other areas.

Calculating Length in Geometry

In geometry, the distance formula is utilized to measure 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 find the distances of the sides AB, BC, and AC. These distances could be utilized to measure other properties of the triangle, such as its area, perimeter and its interior angles.

Solving Problems in Physics

The distance formula is also employed in physics to figure out questions concerning distance, speed, and acceleration. For instance, if we know the original position and velocity of an object, in addition to the time it takes for the object to move a certain distance, we can utilize the distance formula to work out the object's final location and speed.

Analyzing Data in Statistics

In statistics, the length formula is usually utilized to figure out the distances within data points in a dataset. This is useful for clustering algorithms, that group data points that are close to each other, and for dimensionality reduction techniques, this depicts high-dimensional data in a lower-dimensional space.

Go the Distance with Grade Potential

The distance formula is an important idea in math which allows us to figure out the between two points on a plane or in a three-dimensional space. By utilizing the Pythagorean theorem, we can obtain the distance formula and apply it to a magnitude of scenarios, from calculating length on a coordinate plane to analyzing data in statistics.


Comprehending the distance formula and its uses are essential for everyone interested in mathematics and its applications in other areas. If you're struggling with the distance formula or any other math concept, reach out to Grade Potential tutoring for customized guidance. Our experienced instructors will support you master any math topic, from algebra to calculus and furthermore.


Contact us right now to learn more and schedule your first tutoring session.