Identifying Parallel and Perpendicular Lines

Front

What are parallel lines?

Back

Lines that never intersect and have the same slope.

Front

What are perpendicular lines?

Back

Lines that intersect at a right angle (90 degrees) and have slopes that are opposite reciprocals.

Front

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

Back

The slope (m) represents the steepness of the line.

Front

If two lines have slopes m1 and m2, when are they parallel?

Back

They are parallel if m1 = m2.

Front

If two lines have slopes m1 and m2, when are they perpendicular?

Back

They are perpendicular if m1 * m2 = -1.

Front

What is the slope of the line y = 2/3x + 3?

Back

The slope is 2/3.

Front

What is the slope of a line that is perpendicular to y = 2/3x + 3?

Back

The slope is -3/2.

Front

What does it mean for lines to intersect?

Back

Lines intersect if they cross each other at one point.

Front

What is an example of parallel lines?

Back

y = 2x + 1 and y = 2x - 3 are parallel.

Front

What is an example of perpendicular lines?

Back

y = 3x + 1 and y = -1/3x + 2 are perpendicular.