A line has a slope of Negative four-fifths. Which ordered pairs could be points on a line that is perpendicular to this line? Select two options.

(–2, 0) and (2, 5)
(–4, 5) and (4, –5)
(–3, 4) and (2, 0)
(1, –1) and (6, –5)
(2, –1) and (10, 9)

1 answer

To determine which ordered pairs could be points on a line perpendicular to a line with a slope of \(-\frac{4}{5}\), we first need to find the slope of a line that is perpendicular to it.

The product of the slopes of two perpendicular lines is \(-1\). If one slope is \(-\frac{4}{5}\), the perpendicular slope \(m\) can be found as follows:

\[ m \cdot -\frac{4}{5} = -1 \]

Solving for \(m\):

\[ m = \frac{5}{4} \]

Now, the lines that we are checking must have a slope of \(\frac{5}{4}\) in order to be perpendicular to the original line.

We will calculate the slope for the pairs of points given, and see if any pair has a slope of \(\frac{5}{4}\):

  1. For (–2, 0) and (2, 5): \[ \text{slope} = \frac{5 - 0}{2 - (-2)} = \frac{5}{4} \]

  2. For (–4, 5) and (4, –5): \[ \text{slope} = \frac{-5 - 5}{4 - (-4)} = \frac{-10}{8} = -\frac{5}{4} \]

  3. For (–3, 4) and (2, 0): \[ \text{slope} = \frac{0 - 4}{2 - (-3)} = \frac{-4}{5} \]

  4. For (1, –1) and (6, –5): \[ \text{slope} = \frac{-5 - (-1)}{6 - 1} = \frac{-4}{5} \]

  5. For (2, –1) and (10, 9): \[ \text{slope} = \frac{9 - (-1)}{10 - 2} = \frac{10}{8} = \frac{5}{4} \]

From the calculations above, we can see that the pairs of points that produce a slope of \(\frac{5}{4}\) are:

  • (–2, 0) and (2, 5)
  • (2, –1) and (10, 9)

Thus, the two correct options for ordered pairs that could be points on a line that is perpendicular to the original line with slope \(-\frac{4}{5}\) are:

(–2, 0) and (2, 5)
(2, –1) and (10, 9)