Symmetry
Means a figure can be folded into matching halves.
What is line symmetry?
This quadrilateral has 90 degree rotation.
What is a square?
I see this every time I look in the mirror.
My reflection.
This moves a word from one language to another.
What is a translation?
An image is a transformation of this.
What is a pre-image?
This triangle has exactly one line of symmetry.
What is an isosceles triangle?
(6, -1) rotated by 180 degrees.
What is (-6, 1)?
(4, -7) reflected over y = 0.
What is (4, 7)?
Two or more transformations is called this.
What is a composition?
All transformations except dilation preserve this.
What is isometry?
This line of symmetry swaps the coordinates of any point, turning (a,b) into (b,a).
What is y = x?
(3, 4) rotated by 90 degrees CCW.
What is (-4, 3)?
(2, -5) reflected over y = x.
What is (-5, 2)?
What is a vector?
A shape that can be arranged in a plane to cover the whole plane without overlap.
What is a tessellation?
A regular hexagon has this smallest angle of rotation that maps it onto itself.
What is 60 degrees?
(x, y) --> (y, -x)
What is a 270-degree CCW rotation?
Reflecting across y = 0 and then y = x equals this transformation.
What is a 90-degree CCW rotation?
A vector <-3, 5> will do this.
Moves left 3 units and up 5 units.
A translation and a reflection as a combination.
What is a glide reflection?
This reflection line takes the point (3,−5) to (5, −3).
What is the line y=−x?
A figure that looks the same after being rotated less than 360 degrees has this.
What is rotational symmetry?
Moved across x = 2 and then across x = 7 moves every point 10 units horizontally.
What is a double reflection across parallel lines?
This vector moves P(1, 4) to (6, 4).
What is the vector <5, 0>?
These transformations preserve orientation.
What are translation and rotation?