Point A is at (-5 ,4 )(5,4) and point B is at (-8 ,7 )(8,7). Point A is rotated (3pi)/2 3π2 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
Apr 6, 2018

color(indigo)("Increase in distance due to the rotation " = 8.4065Increase in distance due to the rotation =8.4065

Explanation:

A (-5,4), B(-8,7), " rotated " (3pi)/2 " clockwise about the origin"A(5,4),B(8,7), rotated 3π2 clockwise about the origin

bar(AB) = sqrt((-5+8)^2 + (4-7)^2) = 4.2426¯¯¯¯¯¯AB=(5+8)2+(47)2=4.2426

![https://teacher.desmos.com/activitybuilder/custom/566b16af914c731d06ef1953](useruploads.socratic.org)

A (-5, 4) to A'( -4,-5)

bar(A'B) = sqrt((-4 + 8)^2 + (-5 - 7)^2) = 12.6491

color(indigo)("Increase in distance " = 12.6491 - 4.2426 = 8.4065