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.

Tags

CCSS.HSG.CO.A.1

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.

Tags

CCSS.4.G.A.1

CCSS.HSG.CO.A.1

Front

What is the slope of a line in the form y = mx + b?

Back

In the equation y = mx + b, 'm' represents the slope of the line.

Tags

CCSS.8.EE.B.5

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.

Tags

CCSS.4.G.A.1

CCSS.HSG.CO.A.1

Front

If the slope of one line is 2, what is the slope of a line perpendicular to it?

Back

The slope of a line perpendicular to a line with slope 2 is -1/2.

Tags

CCSS.8.EE.B.6

Front

What does it mean for lines to be neither parallel nor perpendicular?

Back

Lines that are neither parallel nor perpendicular intersect at an angle that is not 90 degrees and do not have the same slope.

Tags

CCSS.4.G.A.1

CCSS.HSG.CO.A.1

Front

How can you determine if two lines are parallel using their equations?

Back

Two lines are parallel if their equations have the same slope (m) in the slope-intercept form y = mx + b.

Tags

CCSS.8.EE.B.6

Front

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

Back

The slopes of two perpendicular lines are negative reciprocals of each other. If one slope is m, the other is -1/m.

Tags

CCSS.HSG.CO.A.1

Front

Given the equations y = 3x + 1 and y = 3x - 4, are these lines parallel, perpendicular, or neither?

Back

These lines are parallel because they have the same slope of 3.

Tags

CCSS.8.EE.B.6

Front

Given the equations y = 4x + 2 and y = -1/4x + 5, are these lines parallel, perpendicular, or neither?

Back

These lines are perpendicular because the slopes are 4 and -1/4, which are negative reciprocals.

Tags

CCSS.8.EE.B.6