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📏 Distance Between Two Points on a Coordinate Plane Lab

The segment joining two points
becomes the hypotenuse
of a Pythagorean right triangle

Move points A and B around the coordinate plane with the sliders. The segment joining them is always the hypotenuse of a right triangle whose legs run horizontal and vertical — and its length can be found exactly with the Pythagorean theorem.

Distance formula between two points: the distance between A(x₁,y₁) and B(x₂,y₂) is the hypotenuse of a right triangle whose legs are the horizontal difference (x₂−x₁) and the vertical difference (y₂−y₁). So distance = √{(x₂−x₁)² + (y₂−y₁)²}.

Point A, x1
Point A, y1
Point B, x5
Point B, y4
If two points are only separated horizontally (vertical difference = 0) or only vertically (horizontal difference = 0), the distance formula just reduces to the absolute value of that one remaining difference.