Geometry 4.G.1
Draw points, lines, line segments, rays, angles (right, acute, obtuse), and perpendicular and parallel lines. Identify these in two-dimensional figures.
Learning Targets
Enduring Understanding
What are the building blocks of geometry?
Essential Questions
Vocabulary (online dictionary)
point, line, line segment, ray, parallel lines, perpendicular lines, intersecting lines, endpoint
About the Math
Points, lines, segments, rays, and angles are the building blocks of the geometry. Point and line are undefined terms because they do not have definitions. We can understand these terms by thinking of examples of what a point and line might look like. A point can be a tip of a pencil; it has position but no dimension. Euclid described a line by saying that through any two points there is always a line and every line contains at least two points.
Line segment is part of a line and it contains two endpoints meaning it has a beginning and endpoints. A line contains an infinite number of points and has no endpoints and goes on and on forever. A ray is part of a line that has one endpoint and extends forever in only one direction.
Parallel lines are lines that never cross and are the same distance apart.
Perpendicular lines intersect to form right angles.
Draw points, lines, line segments, rays, angles (right, acute, obtuse), and perpendicular and parallel lines. Identify these in two-dimensional figures.
Learning Targets
- I can identify and draw an example of point, line, line segment, ray, angle, parallel lines, and perpendicular lines.
Enduring Understanding
What are the building blocks of geometry?
Essential Questions
- How are points, line, line segments alike and how are they different?
- What are parallel lines?
- What are perpendicular lines?
Vocabulary (online dictionary)
point, line, line segment, ray, parallel lines, perpendicular lines, intersecting lines, endpoint
About the Math
Points, lines, segments, rays, and angles are the building blocks of the geometry. Point and line are undefined terms because they do not have definitions. We can understand these terms by thinking of examples of what a point and line might look like. A point can be a tip of a pencil; it has position but no dimension. Euclid described a line by saying that through any two points there is always a line and every line contains at least two points.
Line segment is part of a line and it contains two endpoints meaning it has a beginning and endpoints. A line contains an infinite number of points and has no endpoints and goes on and on forever. A ray is part of a line that has one endpoint and extends forever in only one direction.
Parallel lines are lines that never cross and are the same distance apart.
Perpendicular lines intersect to form right angles.