Parallel and Perpendicular Slopes

Front

What is the slope of a line parallel to the line represented by the equation y = mx + b?

Back

The slope of a line parallel to another line is the same. If the slope of the first line is m, then the slope of the parallel line is also m.

Front

What is the slope of a line perpendicular to the line represented by the equation y = mx + b?

Back

The slope of a line perpendicular to another line is the negative reciprocal of the slope of the first line. If the slope of the first line is m, then the slope of the perpendicular line is -1/m.

Front

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

Back

Two lines are parallel if their slopes are equal, i.e., m1 = m2.

Front

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

Back

Two lines are perpendicular if the product of their slopes is -1, i.e., m1 * m2 = -1.

Front

What are negative reciprocals?

Back

Two numbers are negative reciprocals if the product of the two numbers is -1. For example, 2 and -1/2 are negative reciprocals.

Front

Given the equation y = 4x + 1, what is the slope?

Back

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

Front

What is the slope of a line parallel to the line represented by y = -2x + 5?

Back

The slope of a line parallel to y = -2x + 5 is -2.

Front

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

Back

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

Front

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

Back

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

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.