In analytic geometry, the distance between two points of the xy-plane can be found using the distance formula. Distance Formula is used to calculate the distance between two points. The distance between (x1, y1) and (x2, y2) is given by:
\[\large d=\sqrt{\left(x_{2}-x_{1}\right)^{2}+\left(y_{2}-y_{1}\right)^{2}}\]
Example For The Distance Formula
Question: Given the points (-1, -2) and (-3, 5), find the distance between them.
Solution:
Label the points as follows
$\left(x_{1},y_{1}\right)=\left(-1, -2\right) and \left(x_{2},y_{2}\right)=\left(-3, 5\right)$
Therefore:Â $x_{1}=-1,\: y_{1}=-2,\: x_{2}=-3, and\: y_{2}=5$
To find the distance (d) between the points, use the distance formula:
$d=\sqrt{\left(x_{2}-x_{1}\right)^{2}+\left(y_{2}-y_{1}\right)^{2}}$
\(=\sqrt{\left(-3-\left(-1\right)\right)^{2}+\left(5-\left(-2\right)\right)^{2}}\)$=\sqrt{\left(-3+1\right)^{2}+\left(5+2\right)^{2}}$
$=\sqrt{\left(-2\right)^{2}+\left(7\right)^{2}}$
$=\sqrt{4+49}$
$=\sqrt{53}$