WU: Parallel and Perpendicular lines

Front

What are parallel lines?

Back

Parallel lines are lines in a plane that never meet; they have the same slope.

Front

What are perpendicular lines?

Back

Perpendicular lines are lines that intersect at a right angle (90 degrees); their slopes are opposite reciprocals.

Front

How do you determine if two lines are parallel using their equations?

Back

Two lines are parallel if they have the same slope in their slope-intercept form (y = mx + b).

Front

How do you determine if two lines are perpendicular using their slopes?

Back

Two lines are perpendicular if the product of their slopes is -1.

Front

What is the slope of a line given in the form y = mx + b?

Back

The slope (m) is the coefficient of x in the equation.

Front

If a line has a slope of 3, what is the slope of a line perpendicular to it?

Back

The slope of a line perpendicular to a line with slope 3 is -1/3.

Front

What is the slope of a line that is parallel to a line with slope -2?

Back

The slope of a line parallel to a line with slope -2 is also -2.

Front

What does it mean for two lines to be skew lines?

Back

Skew lines are lines that do not intersect and are not parallel; they exist in different planes.

Front

How can you identify parallel lines in a coordinate plane?

Back

Parallel lines in a coordinate plane will have the same slope and different y-intercepts.

Front

What is the relationship between the slopes of two perpendicular lines?

Back

The slopes of two perpendicular lines are negative reciprocals of each other.