Parallel and Perpendicular Lines

Front

What are perpendicular lines?

Back

Lines that intersect at a right angle (90 degrees) and have slopes that are opposite reciprocals.

Front

What is the slope of a line parallel to y = 3x + 4?

Back

3 (Parallel lines have the same slope).

Front

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

Back

1/2 (The slope is the negative reciprocal of -2).

Front

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

Back

They are parallel lines.

Front

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

Back

4 (The slope is the coefficient of x).

Front

How do you find the slope of a line given two points (x1, y1) and (x2, y2)?

Back

Slope (m) = (y2 - y1) / (x2 - x1).

Front

What is the equation of a line that is parallel to y = -x + 3 and passes through the point (2, 1)?

Back

y = -x + 3 (Same slope, different y-intercept).

Front

What does it mean if two lines are neither parallel nor perpendicular?

Back

They intersect at an angle that is not 90 degrees and have different slopes.

Front

What is the relationship between the slopes of two perpendicular lines?

Back

The product of their slopes is -1.

Front

If a line has a slope of 0, what type of line is it?

Back

A horizontal line.