Parallel and Perpendicular Lines of Equations

Front

What are parallel lines?

Back

Parallel lines are lines in a plane that never meet. They have the same slope but different y-intercepts.

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.

Front

If two lines have the same slope, what can we say about them?

Back

If two lines have the same slope, they are parallel.

Front

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

Back

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

Front

What is the slope of the line y = 4x + 1?

Back

The slope of the line y = 4x + 1 is 4.

Front

Determine if the lines y = 2x + 3 and y = 2x - 5 are parallel, perpendicular, or neither.

Back

The lines y = 2x + 3 and y = 2x - 5 are parallel because they have the same slope (2).

Front

Determine if the lines y = -3x + 1 and y = 1/3x + 2 are parallel, perpendicular, or neither.

Back

The lines y = -3x + 1 and y = 1/3x + 2 are perpendicular because their slopes (-3 and 1/3) are negative reciprocals.

Front

What is the slope of a line parallel to y = -5x + 4?

Back

The slope of a line parallel to y = -5x + 4 is -5.

Front

What is the slope of a line perpendicular to y = 1/2x - 3?

Back

The slope of a line perpendicular to y = 1/2x - 3 is -2.

Front

If two lines are neither parallel nor perpendicular, what can we say about their slopes?

Back

If two lines are neither parallel nor perpendicular, their slopes are different and not negative reciprocals.