Transformation Rules

180 degree rotation

Change both signs: (x,y) to (-x,-y)

90 degree clockwise

Switch x and y, then make the new y negative: (x,y) to (y,-x)

90 degree counterclockwise

Switch x and y, then make the new x negative: (x,y) to (-y,x)

270 degree clockwise

Same as 90 counterclockwise: (x,y) to (-y,x)

270 degree counterclockwise

Same as 90 clockwise: (x,y) to (y,-x)

Reflect over x-axis

Change the y sign: (x,y) to (x,-y)

Reflect over y-axis

Change the x sign: (x,y) to (-x,y)

Reflect over y=x

Switch x and y: (x,y) to (y,x)

Reflect over y=-x

Switch x and y and change both signs: (x,y) to (-y,-x)

Reflect over y=a

Move the same distance across the horizontal line; x stays the same