Parallel and Perpendicular Lines

Front

What is the definition of parallel lines?

Back

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

Front

What is the definition of 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 a line has a slope of 2, what is the slope of a line that is parallel to it?

Back

The slope of a line that is parallel to it is also 2.

Front

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

Back

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

Front

Write the equation of a line parallel to y = 2x + 3 that passes through the point (1, 4).

Back

y = 2x + 2.

Front

Write the equation of a line perpendicular to y = -1/2x + 1 that passes through the point (2, 3).

Back

y = 2x - 1.

Front

What is the slope of the line represented by the equation y = 4x - 7?

Back

The slope is 4.

Front

What is the slope of the line represented by the equation y = -3x + 5?

Back

The slope is -3.

Front

If two lines have slopes of 1/4 and 4, are they parallel, perpendicular, or neither?

Back

They are perpendicular.

Front

What is the equation of a horizontal line?

Back

The equation of a horizontal line is of the form y = b, where b is a constant.