Questions and Answers
What describes parallel lines?
What are skew lines?
Lines that do not intersect and are not in the same plane.
What are parallel planes?
Planes that never intersect.
Define a transversal.
Signup and view all the answers
What are interior angles?
Signup and view all the answers
What are exterior angles?
Signup and view all the answers
Define consecutive interior angles.
Signup and view all the answers
What are alternate interior angles?
Signup and view all the answers
What are alternate exterior angles?
Signup and view all the answers
Define corresponding angles.
Signup and view all the answers
The Corresponding Angles Postulate states that if two parallel lines are cut by a transversal, then each pair of corresponding angles is congruent.
Signup and view all the answers
The Alternate Interior Angles Theorem states that if two parallel lines are cut by a transversal, then each pair of alternate interior angles is congruent.
Signup and view all the answers
Consecutive Interior Angles Theorem states that if two parallel lines are cut by a transversal, then each pair of consecutive interior angles is supplementary.
Signup and view all the answers
The Alternate Exterior Angles Theorem states that if two parallel lines are cut by a transversal, then each pair of alternate exterior angles is congruent.
Signup and view all the answers
What is the slope of a line?
Signup and view all the answers
The slope of a vertical line is defined and equal to zero.
Signup and view all the answers
The slope of a horizontal line is equal to zero.
Signup and view all the answers
A line with positive slope rises from left to right.
Signup and view all the answers
A line with negative slope falls from left to right.
Signup and view all the answers
What is the rate of change?
Signup and view all the answers
Two non-vertical lines are parallel if and only if they have different slopes.
Signup and view all the answers
Two non-vertical lines are perpendicular if and only if the product of their slopes is equal to -1.
Signup and view all the answers
What is the y-intercept?
Signup and view all the answers
What is the equation of a horizontal line?
Signup and view all the answers
What is the equation of a vertical line?
Signup and view all the answers
If two lines are cut by a transversal so that corresponding angles are congruent, then the lines are parallel.
Signup and view all the answers
Define the distance between a point and a line.
Signup and view all the answers
What is the Perpendicular Postulate?
Signup and view all the answers
What is the distance formula for the distance between two points?
Signup and view all the answers
What does it mean for two lines to be equidistant?
Signup and view all the answers
What is the distance between parallel lines?
Signup and view all the answers
If two lines are each equidistant from a third line, then the two lines are parallel to each other.
Signup and view all the answers
Study Notes
Parallel and Perpendicular Lines
- Parallel Lines: Never intersect and exist in the same plane.
- Skew Lines: Do not intersect and are not in the same plane.
- Parallel Planes: Planes that never meet.
Angles Formed by Transversals
- Transversal: A line that crosses two or more other lines at varying points.
- Interior Angles: Found between two parallel lines.
- Exterior Angles: Located outside two parallel lines.
- Consecutive Interior Angles: Same-side angles inside parallel lines; supplementary (sum to 180 degrees).
- Alternate Interior Angles: Opposite-side angles inside parallel lines; congruent if lines are parallel.
- Alternate Exterior Angles: Opposite-side angles outside parallel lines; congruent if lines are parallel.
- Corresponding Angles: Matching position angles across parallel lines concerning the transversal; congruent if lines are parallel.
Angle Theorems and Postulates
- Corresponding Angles Postulate: If parallel lines are cut by a transversal, each pair of corresponding angles is congruent.
- Alternate Interior Angles Theorem: If two parallel lines are cut by a transversal, alternate interior angles are congruent.
- Consecutive Interior Angles Theorem: If two parallel lines are cut by a transversal, consecutive interior angles sum to 180 degrees.
- Alternate Exterior Angles Theorem: If two parallel lines are cut by a transversal, alternate exterior angles are congruent.
Slope and Line Characteristics
- Slope Definition: Represents the ratio of vertical change (rise) to horizontal change (run).
- Vertical Line Slope: Undefined slope due to a zero denominator.
- Horizontal Line Slope: Slope equals zero since there's no vertical change.
- Positive Slope: Line rises from left to right.
- Negative Slope: Line falls from left to right.
- Rate of Change: Measures how one variable changes concerning another.
Slopes of Parallel and Perpendicular Lines
- Postulate: Slopes of Parallel Lines: Non-vertical lines are parallel if they share the same slope (m1 = m2).
- Postulate: Slopes of Perpendicular Lines: Non-vertical lines are perpendicular if the product of their slopes equals -1 (m1 * m2 = -1).
Line Equations
- Equation of a Horizontal Line: Represented as y = b, where y is constant.
- Equation of a Vertical Line: Represented as x = a, where x is constant.
Relationships Between Angles and Lines
- Converse of Corresponding Angles: If corresponding angles are congruent when two lines are cut by a transversal, the lines are parallel.
- Distance Between a Point and a Line: Measured by the length of the perpendicular segment from the point to the line.
- Perpendicular Postulate: For a given line, there exists exactly one line perpendicular to it through any point not on that line.
- Distance Between Parallel Lines: Calculated as the perpendicular distance from one line to any point on the other line.
Equidistance and Parallelism
- Equidistant Lines: Two lines are equidistant if they maintain the same distance from each other at all points.
- Theorem: Two Lines Equidistant from a Third Line: If two lines are equidistant from a third line in a plane, they are parallel.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Description
Test your knowledge on parallel and perpendicular lines with these flashcards. Learn key definitions such as parallel lines, skew lines, and transversals to enhance your understanding of geometry concepts. Perfect for revision and quick reference.
