Important Facts

The subsequent facts are used frequently in plane geometry. Those facts will help you solve problems in this section.

1. The shortest distance among two points is the length of the straight line segment joining them.

2. A straight line segment can be extended indefinitely in both directions.

3. Only one straight line segment can be drawn among two points.

4. A geometric figure can be moved in the plane without any effect on its size or shape.

5. Two straight lines in the same plane are either parallel or they intersect.

6. Two lines parallel to a third line are parallel to each other.