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). Their slopes are opposite reciprocals.

Front

If two lines have slopes of 2 and -1/2, what are they?

Back

They are perpendicular lines because their slopes are opposite reciprocals.

Front

If two lines have slopes of 3 and 3, what are they?

Back

They are parallel lines because they have identical slopes.

Front

What is the slope of a line parallel to the line y = 4x + 1?

Back

The slope is 4, as parallel lines have the same slope.

Front

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

Back

The slope is 1/2, as it is the opposite reciprocal of -2.

Front

Are the lines represented by the equations y = 1/3x + 2 and y = 1/3x - 4 parallel, perpendicular, or neither?

Back

They are parallel because they have the same slope of 1/3.

Front

What is the relationship between the slopes of two lines that are neither parallel nor perpendicular?

Back

Their slopes are neither identical nor opposite reciprocals.

Front

If the slope of one line is 0, what can be said about its relationship to another line?

Back

If another line has a slope of 0, they are parallel; if it has an undefined slope, they are perpendicular.

Front

What is the slope of the line y = -5?

Back

The slope is 0, indicating a horizontal line.