Answer:
7 units
Step-by-step explanation:
Distance between 2 points
=[tex] \sqrt{(y1 - y2)^{2} + (x1 - x2) {}^{2} } [/tex]
Thus, distance PQ
[tex] =\sqrt{(8 - 1)^{2} + (7 - 7)^{2} } \\ = \sqrt{7^{2} } \\ = 7[/tex]
Or you could simply take 8-1= 7 since both points have the same x-coordinate. Thus, PQ is a vertical line and the distance between them is due to the difference in their y-coordinate.
