Points, Lines, Rays & Line Relationships

How the lesson starts: Points, Lines, Rays & Line Relationships

Conductor Pia's toy town
Choo choo! Conductor Pia is building a toy train town. She needs train tracks, roads, and crossings. Each one uses a special kind of line. Let's help Pia build her town!
Point, segment, ray, line
A point is a dot that marks one spot. A segment has two endpoints, like one train car. A ray starts at one endpoint and shines on forever, like a flashlight beam. A line goes on forever both ways!
Which roads are perpendicular?
Perpendicular lines cross at a square corner, exactly 90°. Pia checks three pairs of roads. Pair 1 never meets. Pair 2 crosses at 90°. Pair 3 crosses at 50°. Only Pair 2 makes a square corner, so it's perpendicular!