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 perpendicular lines are negative reciprocals of each other.

Front

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

Back

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

Front

If the slopes of two lines are negative reciprocals, what can we say about them?

Back

If the slopes of two lines are negative reciprocals, they are perpendicular.

Front

What is the slope of a line perpendicular to y = 3x - 12?

Back

The slope of a line perpendicular to y = 3x - 12 is -1/3.

Front

Write the equation of a line that is parallel to y = 2x + 5 and passes through the point (1, 3).

Back

y = 2x + 1.

Front

Write the equation of a line that is perpendicular to y = -4x + 7 and passes through the point (2, 1).

Back

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

Front

Are the lines y = 5x + 3 and y = 5x - 2 parallel, perpendicular, or neither?

Back

They are parallel.

Front

Are the lines y = -2x + 4 and y = (1/2)x - 1 perpendicular, parallel, or neither?

Back

They are perpendicular.

Front

What is the y-intercept of the line y = 3x + 6?

Back

The y-intercept is 6.