7.1-Distance Formula
7.1-Distance Formula Important Formulae
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Grade 10 → Math → Coordinate Geometry → 7.1-Distance Formula
- Apply and derive distance formula in order to determine the distance between two coordinates on the graph.
- Apply distance formula in order to solve various mathematical and real-life situations graphically.
The distance formula is a fundamental concept in coordinate geometry that allows us to calculate the distance between two points in a Cartesian plane. If we have two points, $A(x_1, y_1)$ and $B(x_2, y_2)$, the distance $d$ between these two points can be derived from the Pythagorean theorem.
According to the Pythagorean theorem, the distance between two points can be represented as the hypotenuse of a right triangle formed by the horizontal and vertical distances between the points. The formula for calculating the distance is given by:
$d = \sqrt{(x_2 - x_1)^2 + (y_2 - y_1)^2}$
Here:
- $d$ = Distance between points $A$ and $B$
- $(x_1, y_1)$ = Coordinates of point $A$
- $(x_2, y_2)$ = Coordinates of point $B$
To illustrate the distance formula, let's consider an example. Suppose we have two points:
Point $A(3, 4)$ and Point $B(7, 1)$. We will calculate the distance between these points.
Using the distance formula:
$d = \sqrt{(7 - 3)^2 + (1 - 4)^2}$
Calculating each part:
$d = \sqrt{(4)^2 + (-3)^2} = \sqrt{16 + 9} = \sqrt{25} = 5$
Therefore, the distance between points $A(3, 4)$ and $B(7, 1)$ is $5$ units.
The distance formula can also be applied to find the distance between points in three-dimensional space. If we have two points $A(x_1, y_1, z_1)$ and $B(x_2, y_2, z_2)$ in 3D, the formula extends to:
$d = \sqrt{(x_2 - x_1)^2 + (y_2 - y_1)^2 + (z_2 - z_1)^2}$
For instance, if we consider points $A(1, 2, 3)$ and $B(4, 6, 8)$, we can calculate the distance as follows:
$d = \sqrt{(4 - 1)^2 + (6 - 2)^2 + (8 - 3)^2}$
Calculating this gives:
$d = \sqrt{(3)^2 + (4)^2 + (5)^2} = \sqrt{9 + 16 + 25} = \sqrt{50} = 5\sqrt{2}$
The distance formula is widely used in various applications, including physics, engineering, and computer graphics. It helps in determining lengths, trajectories, and more in both two-dimensional and three-dimensional spaces.
Understanding how to apply the distance formula allows for solving real-world problems that involve measurement of distances, ensuring accuracy in calculations and representations.
Jim.belk, Public domain, via Wikimedia Commons