Given:
The two points are [tex](x_1,y_1)[/tex] and [tex](x_2,y_2)[/tex].
To find:
The distance between given points.
Solution:
Plot the two points [tex](x_1,y_1)[/tex] and [tex](x_2,y_2)[/tex] randomly randomly on a coordinate plane, then form a right angle triangle as shown in the below figure.
Now, the hypotenuse is the distance between the two points.
[tex]\text{Perpendicular}=y_2-y_1[/tex]
[tex]\text{Base}=x_2-x_1[/tex]
Using Pythagoras theorem,
[tex]\text{Hypotenuse}^2=\text{Base}^2+\text{Perpendicular}^2[/tex]
[tex]d^2=(x_2-x_1)^2+(y_2-y_1)^2[/tex]
Taking square root on both sides, we get
[tex]d=\sqrt{(x_2-x_1)^2+(y_2-y_1)^2}[/tex] [Distance is always positive]
Therefore, the distance between the two points is [tex]d=\sqrt{(x_2-x_1)^2+(y_2-y_1)^2}[/tex]. It is also known as distance formula.
