Parallel and Perpendicular Lines

Front

What are parallel lines?

Back

Parallel lines are lines in a plane that never meet. They have the same slope but different y-intercepts.

Front

What are perpendicular lines?

Back

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

Front

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

Back

If two lines have the same slope, they are parallel.

Front

If the slope of one line is m, what is the slope of a line perpendicular to it?

Back

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

Front

What is the slope of the line y = 5/7x + 2?

Back

The slope of the line y = 5/7x + 2 is 5/7.

Front

What is the slope of the line y = -7/2x + 4?

Back

The slope of the line y = -7/2x + 4 is -7/2.

Front

Are the lines y = 6x + 2 and y = -6x + 2 parallel, perpendicular, or neither?

Back

The lines y = 6x + 2 and y = -6x + 2 are neither.

Front

Which of the following lines are parallel: y = 2x + 1 and y = -1/2x + 1?

Back

The lines y = 2x + 1 and y = -1/2x + 1 are not parallel.

Front

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

Back

The equation of the line is y = 3x - 1.

Front

What is the relationship between the slopes of the lines y = 3x + 1 and y = 3x - 4?

Back

The lines y = 3x + 1 and y = 3x - 4 are parallel because they have the same slope.