Parallel and Perpendicular Lines

Front

What is the slope of a line that is perpendicular to a line with slope m = 5/8?

Back

-8/5

Front

What is the slope of a line that is perpendicular to a line with slope m = -3?

Back

1/3

Front

What do we call the slopes of perpendicular lines?

Back

Opposite reciprocals.

Front

Write the equation of a line perpendicular to y = 3x - 8 that passes through the point (-3, -9).

Back

y + 9 = -1/3(x + 3)

Front

Write the equation of a line parallel to y = -1/2x + 3 that goes through the point (4, -1).

Back

y + 1 = -1/2(x - 4)

Front

Define parallel lines in terms of slope.

Back

Parallel lines have the same slope.

Front

Define perpendicular lines in terms of slope.

Back

Perpendicular lines have slopes that are opposite reciprocals.

Front

What is the opposite reciprocal of 2?

Back

-1/2

Front

If a line has a slope of 0, what can be said about its orientation?

Back

It is a horizontal line.

Front

If a line has an undefined slope, what can be said about its orientation?

Back

It is a vertical line.