Question

If a line has an undefined slope, what type of line is it classified as? (Check your spelling!)

Answer 1

The slope of a line can be positive, negative, zero, or undefined. A horizontal line has slope zero since it does not rise vertically (i.e. y1 − y2 = 0), while a vertical line has undefined slope since it does not run horizontally (i.e. x1 − x2 = 0)