Geometry Dilations Chapter 8 Unit

A dilation is a transformation that produces an image that is the same ___

shape

A dilated image figures are not congruent they are _______

similar to the original figure.

The side lengths will change, but _____ measures do not change, to preserve the shapes of the figures.

angle

Dilations are not ____

rigid motion

rigid motion

transformation that maintains distance and angle measures, preserving the shape and size of the figure.

Isometry

a transformation that preserves distances and angles, meaning the shape and size of figures remain unchanged.

A dilation that creates a larger image is called a

enlargement.

A dilation that creates a smaller image is called a

reduction.

K is equal to

scale factor

scale factor

the ratio of the lengths of the corresponding sides of the image and the pre-image

image over original equals

K FORMULA

If the scale factor is greater than 1, the image is

an enlargement of the image

If the scale factor is between 0 and 1, the image is

a reduction of the image

If the scale factor is 1

the figure and the image are congruent

If the scale factor is negative, the image will be _____ and ______ ___ degrees

dilated and rotated 180 degrees

center of dilation

a fixed point from which we measure the distances to points

Origin

Most dilations in the coordinate plane use this as the center of dilation

Coordinate Rule

If a point (x,y) is dilated around to the origin and has a scale factor k, then its image will be the point (Kx, Ky). You just multiply all coordinates by K