Parallel and Perpendicular Lines

Front

What is the slope of a line parallel to a line with slope m?

Back

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

Front

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

Back

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

Front

What is the slope of a line with a positive slope?

Back

A line with a positive slope rises from left to right.

Front

What is the slope of a line with a negative slope?

Back

A line with a negative slope falls from left to right.

Front

What does a slope of zero indicate about a line?

Back

A slope of zero indicates a horizontal line.

Front

What does an undefined slope indicate about a line?

Back

An undefined slope indicates a vertical line.

Front

If two lines are parallel, what can be said about their slopes?

Back

If two lines are parallel, their slopes are equal.

Front

If two lines are perpendicular, what can be said about their slopes?

Back

If two lines are perpendicular, the product of their slopes is -1.

Front

What is the slope of a line that is horizontal?

Back

The slope of a horizontal line is 0.

Front

What is the slope of a line that is vertical?

Back

The slope of a vertical line is undefined.