As the slope is -1, so any line that has the same slope is parallel.
Solution:
Given points (2, -7) and (4, -9) find the slope, m:
[tex]m = \frac{y - y_1}{x - x_1}[/tex]
[tex]\Rightarrow m = \frac{-7 - (-9)}{2 - 4}[/tex]
[tex]m = \frac{-7 + 9}{-2}[/tex]
[tex]m = \frac{2}{-2}=-1[/tex]
Any line that has the same slope is parallel.