Understanding Parallel and Perpendicular Lines

What is the relationship between the slopes of parallel lines?

• They intersect at a 90° angle.

• One slope is the negative reciprocal of the other.

• They have the same slope.

• They have different slopes.

If a line has a slope of 2, what must be true for another line to be parallel to it?

• The other line must have a slope of -2.

• The other line must have a slope of 1/2.

• The other line must have a slope of 2.

• The other line must have a slope of 0.

Why can't two lines with different slopes be parallel?

• They form a 90° angle.

• They have the same y-intercept.

• They will never intersect.

• They will eventually intersect.

What happens to two lines if one of their slopes is slightly increased?

• They have the same y-intercept.

• They become perpendicular.

• They intersect.

• They remain parallel.

What is a defining characteristic of perpendicular lines?

• They never intersect.

• They have the same slope.

• They have the same y-intercept.

• They intersect at a 90° angle.

How do you find the slope of a line perpendicular to another line with a slope of 3?

• The slope is -3.

• The slope is -1/3.

• The slope is 3.

• The slope is 1/3.

If a line has a slope of 1/2, what is the slope of a line perpendicular to it?

• 2

• 1/2

• -1/2

• -2

What is the slope of a line that is perpendicular to a line with a slope of -4?

• 1/4

• -4

• -1/4

• 4

Which of the following is true about the slopes of perpendicular lines?

• They are equal.

• They are both positive.

• They are both negative.

• They are negative reciprocals.

What is the slope of a line perpendicular to a line with a slope of 5?

• -5

• 1/5

• -1/5

• 5