Point A is at (9 ,3 ) and point B is at (1 ,-3 ). Point A is rotated pi/2 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(green)("Change in distance " = 2.65 " units")

Explanation:

A (9, 3), B (1, -3), "Point A rotated about origin clockwise by " (pi/2)

To find change in distance between A & B due to this rotation.

Using distance formula,

vec(AB) = sqrt ((9-1)^2 + (3 + 3)^2) = 10

![http://www.scielo.org.za/scielo.php

A((9),(3)) -> A'((-3),(9))

vec(A'B) = sqrt((-3-1)^2 + (9+3)^2) = 12.65

"Change in distance =" = vec(A'B) - vec(AB) = 12.65 - 10 = 2.65