How To Tell If Two Lines Are Parallel, Perpendicular, or Neither?

What is true about the slopes of two parallel lines?

• They are negative reciprocals of each other.

• They are the same.

• They multiply to 1.

• They are always positive.

If a line has a slope of 4/3, what is the slope of a line perpendicular to it?

• 4/3

• -4/3

• 3/4

• -3/4

At what angle do perpendicular lines intersect?

• 45 degrees

• 90 degrees

• 180 degrees

• They do not intersect

Consider the lines given by the equations Y = 2x - 3 and Y = 3x + 1. How would you describe the relationship between these two lines?

• Parallel

• Perpendicular

• Neither parallel nor perpendicular

• Identical