http://www.ck12.org Chapter 12. Rigid Transformations
Example C
Find the coordinates ofABCDafter a 270◦rotation counter-clockwise about the origin.
Using the rule, we have:
(x,y)→(y,−x)
A(− 4 , 5 )→A′( 5 , 4 )
B( 1 , 2 )→B′( 2 ,− 1 )
C(− 6 ,− 2 )→C′(− 2 , 6 )
D(− 8 , 3 )→D′( 3 , 8 )
Watch this video for help with the Examples above.