December 30, 2022

Distance Between Two Points - Formula, Derivation, Examples

The concept of length is critical in both math and routine life. From straightforward measuring the length of a line to calculating the shortest route among two points, understanding the distance within two points is vital.


In this blog, we will take a look at the formula for distance between two points, go through some examples, and discuss realistic applications of this formula.

The Formula for Length Within Two Points

The length among two points, often indicated as d, is the length of the line segment connecting the two points.


In math, this could be depicted by drawing a right triangle and employing 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 as same as the length, d.


In the case of working out the length within two locations, we could represent the points 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 then utilize the Pythagorean theorem to acquire the ensuing 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 length along y-axis, forming a right angle. By considering the square root of the sum of their squares, we get the distance between the two points.


Here is a visual illustration:


Instances of Utilizations of the Distance Formula

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

Working out the Distance Between Two Locations on a Coordinate Plane

Imagine we have two extremities on a coordinate plane, A with coordinates (3, 4) and B with coordinates (6, 8). We will use the distance formula to calculate the distance between these two points as ensues:


d = √((6 - 3)2+ (8 - 4)2)

d = √(32 + 42)

d = √(9 + 16)

d = √(25)

d = 5


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

Calculating the Distance Among Two Points on a Map

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


To find the length within two points on the map, for instance the airport and the city hall, we can simply work out the length among the two points using a ruler and convert the measurement to miles using the map's scale.


While we calculate the length among these two points 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 among the city hall and the airport is 20 miles.

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

In addition to calculating lengths in two dimensions, we could also use the distance formula to figure out the distance among two locations in a three-dimensional space. For example, assume we have 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 figure out the distance within these two points as ensuing:

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


Utilizing this formula, we can calculate the distance among any two points in three-dimensional space. For instance, if we have two locations A and B with coordinates (1, 2, 3) and (4, 5, 6), respectively, we could work out the length between them as follows:


d = √((4 - 1)2 + (5 - 2)2 + (6 - 3)2)

d = √(32 + 32 + 32)

d = √(9 + 9 + 9)

d = √(27)

d = 3.16227766


Thus, the distance within locations A and B is just about 3.16 units.

Utilizations of the Distance Formula

Now once we have seen some instances of utilizing the distance formula, let's study some of its Utilizations in math and other areas.

Calculating Length in Geometry

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

Solving Problems in Physics

The distance formula is additionally used in physics to figure out problems concerning distance, speed, and acceleration. For example, if we know the original position and velocity of an object, in addition to the time it requires for the object to transport a certain distance, we could use the distance formula to calculate the object's concluding position and speed.

Analyzing Data in Statistics

In statistics, the length formula is frequently utilized to figure out the distances between data points in a dataset. This is useful for clustering algorithms, which group data points which are near to each other, and for dimensionality reduction techniques, which portrays 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 work out the within two location on a plane or in a three-dimensional space. By using the Pythagorean theorem, we could extract the distance formula and apply it to a magnitude of situations, from measuring length on a coordinate plane to analyzing data in statistics.


Understanding the distance formula and its uses are important for everyone interested in math and its applications in other fields. If you're struggling with the distance formula or any other math concept, connect with Grade Potential tutoring for tailored help. Our experienced instructors will help you master any math topic, from algebra to calculus and furthermore.


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