Line N passes through the points (–1, 4) and (–1, –4). A coordinate plane. Which is true of line N?
Line N is a vertical line with an undefined slope.
Line N is a vertical line with a slope of zero.
Line N is a horizontal line with an undefined slope.
Line N is a horizontal line with a slope of zero.

line Number is a vertical line with an undefined slope

Step-by-step explanation:

Slope, m

= (change in y) / (change in x)

= (y - y1) / (x - x1)

Points are represented as coordinates, (x, y)

Given point 1 ( -1, 4), point 2 ( -1, -4)

These correspond to (x1, y1) and (x, y) respectively

m = (-4 - 4) / (-1 - (-1))

m = -8 / 0

Slope, m is undefined

At a constant value of x in the x-axis on a Cartesian plane, the slope of the line is undefined