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

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Back

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Back

Front

What is the slope of a line with a slope of 3/4?

Back

The slope of the line is 3/4.

Front

What is the slope of a line parallel to a line with slope -1/7?

Back

The slope of a line parallel to a line with slope -1/7 is also -1/7.

Front

What is the slope of a line perpendicular to a line with slope 5?

Back

The slope of a line perpendicular to a line with slope 5 is -1/5.

Front

If a line has a slope of -6/5, what is the slope of a line perpendicular to it?

Back

The slope of a line perpendicular to a line with slope -6/5 is 5/6.

Front

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

Back

The slopes of two parallel lines are equal.

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.