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 the slope of a 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 = 2x + 3?

Back

The slope of the line y = 2x + 3 is 2.

Front

Which line is perpendicular to y = 3x + 1?

Back

A line with slope -1/3 is perpendicular to y = 3x + 1.

Front

What is the slope of the line y = -4x + 5?

Back

The slope of the line y = -4x + 5 is -4.

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

What is the y-intercept of the line y = 5x - 2?

Back

The y-intercept of the line y = 5x - 2 is -2.

Front

Determine if the lines y = 1/2x + 3 and y = -2x + 1 are parallel, perpendicular, or neither.

Back

The lines are perpendicular because the slopes (1/2 and -2) are negative reciprocals.

Front

What is the equation of a line parallel to y = 2x + 4 with a y-intercept of 1?

Back

The equation is y = 2x + 1.