Virginia SOL Math / Grade 4 / Measurement & Geometry
Points, Lines, Rays & Angles
What you'll learn
- Identify and describe points, lines, line segments, rays, and angles
- Identify parallel, perpendicular, and intersecting lines
- Classify angles as right, acute, or obtuse
Words to know
- Point —
- an exact location, shown as a dot
- Line segment —
- part of a line with two endpoints
- Ray —
- part of a line with one endpoint, going on forever
- Angle —
- two rays that share an endpoint
- Parallel —
- lines that never cross
- Perpendicular —
- lines that cross to make right angles
Why it matters These building blocks describe roads, buildings, and designs, and help us talk about how lines and corners meet.
Worked examples
Model ItI do
What is the difference between a line segment and a ray?
A line segment has two endpoints and a set length. A ray has only one endpoint and goes on forever in one direction. Both are parts of a line.
Try It TogetherWe do
An angle opens less than a right angle. What kind of angle is it?
A right angle is a square corner, or 90 degrees. An angle smaller than that is an acute angle.
Now YouYou do
Two lines cross and make square corners. What are they called?
Think about what kind of lines form right angles where they meet. Check your answer in the back.
Practice
Mastered 0 of 11
Warm-up
Ease in with the basics.
1.What is an exact location shown as a dot called?
2.How many endpoints does a line segment have?
3.What kind of angle is a square corner?
On Level
The core Quick Check from the book.
1.How many endpoints does a line segment have?
2.What do you call lines that never cross?
3.What kind of angle is a square corner?
4.Is an angle larger than a right angle acute or obtuse?
5.How many endpoints does a ray have?
Challenge
Stretch your thinking.
1.Two lines cross but do not make right angles. What are they called?
2.An angle opens wider than a right angle but less than a straight line. What kind of angle is it?
3.The rails of a straight train track never cross. What kind of lines are they?