8th Grade · Geometry
Distance
8.G.B.8
Definition
The straight-line length between two points on a coordinate plane, found by applying the Pythagorean theorem to the horizontal and vertical changes.
Examples
- From (0,0) to (4,5) with legs 4 and... wait: distance = √(3²+4²) = √25 = 5.
- Make a right triangle from the horizontal and vertical changes; the distance is the hypotenuse.
Key rule
Use the Pythagorean theorem on the horizontal and vertical legs.
Memory hook
Make a right triangle, then find the hypotenuse.