Grade 4 · Maths · Lessons
Lines, rays and corners
➖line➡️ray🟦parallel📐perpendicular
Lines and angles.The big ideaParallel lines never meet. Perpendicular lines meet at a square corner.
How it works
A ray has one end point. A line segment has two. A line goes on forever both ways.
Parallel lines never meet. Perpendicular lines meet at a square corner.
A square has two pairs of parallel sides.
Example 1: A ray
- A ray starts at point M and goes on through N.
- It has one end point.
- A ray has 1 end point.
Example 2: Pairs in a square
- The top and bottom of a square never meet. The left and right never meet.
- That is 2 pairs.
- A square has 2 pairs of parallel sides.
Example 3: A trapezoid
- Only the top and bottom of a trapezoid are parallel.
- The slanted sides would meet.
- A trapezoid has 1 pair.
Words to know
- ray
- A line with one end point.
- parallel
- Lines that never meet.
- perpendicular
- Lines that meet at a right angle.
Watch out
- A ray has one end point.
- Parallel lines stay the same distance apart.
- Perpendicular means a right angle.
Try it
- How many end points does a line segment have?
- Do parallel lines meet?
- What angle do perpendicular lines make?
- How many pairs of parallel sides does a rectangle have?
Answers: 1. 2 · 2. no · 3. a right angle · 4. 2
For grown-upsHunt for parallel and perpendicular lines in your home: window frames, shelves, doors.