December 30, 2022

Distance Between Two Points - Formula, Derivation, Examples

The concept of distance is critical in both math and everyday life. From easily measuring the length of a line to working out the quickest route between two extremities, understanding the distance within two points is important.


In this blog, we will take a look at the formula for distance within two locations, review some examples, and talk about real-life utilizations of this formula.

The Formula for Distance Between Two Points

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


Mathematically, this can be depicted by drawing a right triangle and employing the Pythagorean theorem. As stated in the Pythagorean theorem, the square of the length 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 distance, d.


In the case of finding the distance between two points, we could depict the points 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 further employ the Pythagorean theorem to extract the following formula for distance:

d = √((x2 - x1)2 + (y2 - y1)2)


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


Here is a graphical depiction:


Examples of Using the Distance Formula

Considering we have the formula for distance, let's check out few examples of how it can be utilized.

Calculating the Length Within 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 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 Among Two Extremities on a Map

In addition to figuring out the distances on a coordinate plane, we could also use the distance formula to figure out distances between two points on a map. For instance, assume we posses a map of a city with 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 work out the distance among the two locations using a ruler and change the measurement to miles using the map's scale.


While we calculate the distance between these two locations on the map, we figure out it is 2 inches. We change this to miles utilizing the map's scale and work out that the true distance between the airport and the city hall is 20 miles.

Determining the Distance Among Two Points in Three-Dimensional Space

In addition to finding lengths in two dimensions, we could also use the distance formula to calculate the length within two points in a three-dimensional space. For example, assume we have two points, A and B, in a three-dimensional space, with coordinates (x1, y1, z1) and (x2, y2, z2), respectively.


We will utilize the distance formula to find the length between these two locations as follows:

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


Using this formula, we can determine the length within 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), 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


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

Applications of the Distance Formula

Now that we have seen some instances of utilizing the distance formula, let's examine 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 use the distance formula to find the distances of the sides AB, BC, and AC. These distances can be utilized to measure other characteristics of the triangle, for instance its area, perimeter and its interior angles.

Solving Problems in Physics

The distance formula is also used in physics to figure out questions concerning distance, speed, and acceleration. For instance, if we perceive the original location and velocity of an object, as well as the time it takes for the object to transport a certain length, we could utilize the distance formula to figure out the object's concluding position and speed.

Analyzing Data in Statistics

In statistics, the length formula is often utilized 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 an essential concept in math that allows us to calculate 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 implement it to a magnitude of scenarios, from calculating distances on a coordinate plane to analyzing data in statistics.


Understanding the distance formula and its utilizations are crucial for anyone fascinated in mathematics and its applications in other fields. If you're struggling regarding the distance formula or any other math concept, connect with Grade Potential tutoring for tailored guidance. Our professional tutors will help you conquer any mathematics topic, from algebra to calculus and furthermore.


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