Point A is at (-2 ,5 )(2,5) and point B is at (2 ,-3 )(2,3). Point A is rotated pi π clockwise about the origin. What are the new coordinates of point A and by how much has the distance between points A and B changed?

1 Answer
Mar 29, 2018

color(blue)("Decrease in distance due rotation is "Decrease in distance due rotation is

color(orange)(vec(AB) - vec(A'B) = 8.94 - 2 = 6.94 " units"

Explanation:

A (-2, 5), B (2, -3)

vec (AB) = sqrt((-2-2)^2 + (5 + 3)^2) = 8.94 " units"

"Point A rotated " pi " clockwise about the origin"

![https://www.onlinemath4all.com/http://rotation-transformation.html](https://useruploads.socratic.org/xMO9M5zOTQarx2Qu3hx8_rotation%20rules.jpg)

A (-2,5) -> A'(2, -5)

vec (A'B) = sqrt ((2-2)^2 + (-5 +3)^2) = 2 " units"

color(blue)("Decrease in distance due rotation is "

color(grey)(vec(AB) - vec(A'B) = 8.94 - 2 = 6.94 " units"