18 terms

pre-image

The original figure in a transformation.

image

The figure that results from a transformation.

triangle A'B'C'

Method of labeling a triangle that results from a transformation. Read as triangle A prime, B prime, C prime.

transformation

To change the properties of a shape.

rotation

A transformation that "turns" a figure about a fixed point at a given angle and a given direction.

translation

A movement (slide) of a figure along a straight line.

reflection

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

dilation

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

clockwise

in the same direction as the rotating hands of a clock

counter-clockwise

In the direction opposite to the rotation of the hands of a clock.

90 degree rotation counter - clockwise

Triangle A'B'C' is the new (rotated) image.

90 degree rotation clockwise

Quadrilateral A'B'C'D' is the new (rotated) image.

180 degree rotation

Triangle A'B'C' is the new (rotated) image.

reflection across the y-axis

Triangle A'B'C' is the new (reflected) image.

reflection across the x-axis

Quadrilateral A'B'C'D' is the new (reflected) image.

Vertical translation

An up or down slide; the y-coordinate changes.

Horizontal translation

A slide to the right or left; the x-coordinate changes.

bisect

to cut in half