Distance Formula

The Distance Formula is a variant of the Pythagorean Theorem that you used back in geometry.

To calculate the distance between two points (x1, y1) and (x2, y2), all that you need to do is to insert the values asked in the formula. The distance formula can be used to find solutions to many real-world problems.

The distance formula is:

Example:

1. Find the distance between (-1, 1) and (3, 4).

This problem is solved simply by putting out x- and y-values into the distance formula:

D=√(3−(−1))²+(4−1)²
=√16+9=√25=5

2. Calculate the distance between the points P(1, 2) and Q(-3, -2).

This problem is solved simply by putting out x- and y-values into the distance formula:

D=√(1−(−3))²+(2−(-2)²)
=√16+16=√32=5.66

Sometimes you need to find the point that is exactly between two other points. This middle point is called the “midpoint”. According to the definition, a midpoint of a line segment is the point on that line segment that divides the segment into two congruent segments. We have mentioned all the things about midpoints in an article before.

You might be thinking that what would happen if you reverse the points? You have to remember that you are dealing with distances, which are inherently positive. The distance is the same in either direction, going from point 1 to point 2 or vice versa. So, just use the positive distance between two points.