# Sign up for an account

Already have a Quizlet account?

Log in.

###
Transformation

a change in the position, size, or shape of a figure

###
Preimage

the original figure

###
Image

a figure resulting from a transformation

###
Isometry

a transformation in which the preimage and image are congruent

###
Translation

A transformation that "slides" each point of a figure the same distance in the same direction.

###
(x+/-a, y+/-b)

Writing Rules for Translations

###
Reflection

A transformation that "flips" a figure over a mirror or reflection line.

###
Line of Reflection

A line that a figure is flipped across to create a mirror image of the original figure

*perpendicular to lines connecting corresponding points of the image and preimage

###
(x, -y)

Rule for Reflection Over X-axis

###
(-x, y)

Rule for Reflection over Y-axis

###
(y, x)

Rule for Reflection Over line y=x

###
Rotation

a transformation in which a figure is turned around a point

-counterclockwise unless stated otherwise

###
(-y, x)

Rule for 90 degree rotation

###
(-x, -y)

rule for 180 degree rotation

###
(y, -x)

rule for 270 degree rotation

###
Dilation

A transformation that changes the size of an object, but not the shape.

-image will always be similar to preimage

###
(nx, ny)

Rule for Dilations

###
n^2 x area of preimage

Area of Image of Dilation

###
add numbers in corresponding positions

-matrices must be same size

(translation)

Adding Matrices

###
multiply the number by every number in matrix

(dilation)

Multiplying Matrices by a Single Number

###
Vertex Matrix

a matrix used to represent the coordinates of the vertices of a polygon

###
[1 0]

[0 -1]

Matrix for Reflection over X-axis

###
[-1 0]

[0 1]

Matrix for Reflection over Y-axis

###
[0 1]

[1 0]

Matrix for Reflection over Y=X

###
[0 -1]

[1 0]

Matrix for 90 degree Rotation

###
[-1 0]

[0 -1]

Matrix for 180 degree Rotation

###
[0 1]

[-1 0]

Matrix for 270 degree Rotation

###
[1 0]

[0 1]

Matrix for 360 degree Rotation

###
the shape is rotated 180 degrees

what happens when you have a scale factor that is negative?

###
connect the corresponding points of the image and preimage and construct the perpendicular bisector

How do you construct the line of reflection?

### Please allow access to your computer’s microphone to use Voice Recording.

## We can’t access your microphone!

### Click the icon above to update your browser permissions and try again

Example:

### Reload the page to try again!

Reload

## Press Cmd-0 to reset your zoom

## Press Ctrl-0 to reset your zoom

### It looks like your browser might be zoomed in or out. Your browser needs to be zoomed to a normal size to record audio.

## Your microphone is muted

### For help fixing this issue, see this FAQ.