Parallel and Perpendicular Lines

Front

What are parallel lines?

Back

Parallel lines are lines in a plane that never meet or intersect. They have the same slope.

Front

What are perpendicular lines?

Back

Perpendicular lines are lines that intersect at a right angle (90 degrees). The slopes of perpendicular lines are negative reciprocals of each other.

Front

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

Back

Two lines are parallel if m1 = m2.

Front

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

Back

Two lines are perpendicular if m1 * m2 = -1.

Front

What is the slope of a line parallel to y = 3x + 2?

Back

The slope of a line parallel to y = 3x + 2 is 3.

Front

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

Back

The slope of a line perpendicular to y = -2x + 5 is 1/2.

Front

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

Back

The slope (m) is calculated as m = (y2 - y1) / (x2 - x1).

Front

What is the equation of a line in slope-intercept form?

Back

The equation of a line in slope-intercept form is y = mx + b, where m is the slope and b is the y-intercept.

Front

What is the y-intercept of the line y = 4x - 1?

Back

The y-intercept of the line y = 4x - 1 is -1.

Front

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

Back

A line with a slope of 0 is a horizontal line.