Equations of parallel and perpendicular

Front

What is the definition of parallel lines in terms of slope?

Back

Parallel lines have the same slope.

Front

What is the definition of perpendicular lines in terms of slope?

Back

Perpendicular lines have slopes that are negative reciprocals of each other.

Front

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

Back

The slope of a line parallel to it is also m.

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 it is -1/m.

Front

What is the slope of the line represented by the equation y = 3x + 2?

Back

The slope is 3.

Front

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

Back

They are parallel because they have the same slope of 2.

Front

Determine if the lines y = -1/2x + 4 and y = 2x - 1 are parallel, perpendicular, or neither.

Back

They are perpendicular because the slopes are -1/2 and 2, which are negative reciprocals.

Front

What is the slope of a line parallel to the line whose equation is 4x + 2y = 8?

Back

First, convert to slope-intercept form: y = -2x + 4. The slope is -2.

Front

What is the slope of a line perpendicular to the line whose equation is y = 5x + 3?

Back

The slope is -1/5.

Front

If two lines have slopes of 1/3 and -3, what can be said about their relationship?

Back

They are perpendicular because their slopes are negative reciprocals.