Transformations

A rule for moving every point in a figure to a new location.

Translation

A transformation that moves each point in a figure the same distance in the same direction.

“SLIDE”

• In a translation a figure slides up or down, or left or right. [There is no change in shape or size. The only thing that changes is location.]

• In graphing translation, all x and y coordinates change by adding or subtracting.

Reflection

A transformation where a figure is flipped across a line such as the x-axis or the y-axis.

“FLIP”

• In a reflection, a mirror image of the figure is formed across a line called a line of symmetry. [There is no change is size, the orientation of the shape changes.]

• In graphing, – reflection across the x -axis changes the sign of the y

coordinate.– reflection across the y-axis changes the sign of the x-

coordinate.

A transformation where a figure turns about a fixed point without changing its size and shape.

Rotation

“TURN”

• In a rotation, figure turns around a fixed point, such as the origin. No change in shape, but the orientation and location change.

Rules for rotating a figure about the origin in graphing.– Rules for 90 degrees rotation - Switch the

coordination of each point. Then change the sign of the y coordinate. Ex. A (2,1) to A’ ( 1,-2)

– Rules for 180 degrees rotation – Coordinate points stay the same, just become opposite signs.

Ex. A (2,1) to A’ (-2, -1)

Dilation

A transformation where a figure changes size.

“SHRINK”

or

“GROW”

• In a dilation, a figure is enlarged or reduced proportionally. No change in shape, but unlike other transformation, the size changes.

• In graphing, for dilation, all coordinates are divided or multiplied by the same number to find the coordinates of the image.