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.
Teach it
Where it is taught, with guided notes, practice, homework, an exit ticket and an interactive Teacher Deck.
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.