Similarities and Transformations
James Richter 9/4/13 3rd period
A transformation is an operation that maps a geometric figure called the preimage, onto a new figure called the image. There are 4 types of transformations: rotations, dilations, reflections, and translations. To find the coordinates of a figure after a rotation of 90 degrees, just switch the x and y coordinates and make the x the opposite. When rotating 180 degrees, change both the x and y coordinates to their opposites. When rotating 270 degrees, switch the x and y coordinates and make the y the opposite. When dilating, just multiply the original coordinates by the scale factor. When reflecting over x, keep the x the same, and make the y the opposite. When reflecting over y, keep the y the same and make the x the opposite. And lastly when translating, just add the original coordinates to the coordinates that you're translating by.
A similarity is when 2 figures have the same angles and same shape, but not the same size. A similarity is similar to a dilation because both of them require a scale factor to solve. A figure that is dilated by a scale factor is a similarity.