Cards

Question 0

Point symmetry

Answer 0

If identical when rotated 180 degrees upside down

Question 1

Line symmetry

Answer 1

Congruent if folded horizontally vertically or diagonally along an imaginary line

Question 2

r x-axis

Answer 2

Reflect over x axis, negate y

Question 3

r y-axis

Answer 3

Reflect over y axis negate x

Question 4

r y=x

Answer 4

Diagonal up, flip (y,x)

Question 5

r y=-x

Answer 5

Diagonal down, flip/negate both (-y,-x)

Question 6

What is not preserved in a line reflection?

Answer 6

Orientation

Question 7

R 360

Answer 7

Original (a,b)

Question 8

R 90

Answer 8

(-b,a)

Question 9

R 180

Answer 9

(-a,-b) same as point reflection through origin

Question 10

R 270

Answer 10

(b,-a)

Question 11

R -270

Answer 11

(-b,a)

Question 12

R -180

Answer 12

(-a,-b)

Question 13

R -90

Answer 13

(b,-a) negatives go clockwise

Question 14

What is preserved under rotation?

Answer 14

Distance, orientation, midpoint, collinearity, angle measure

Question 15

Rotational symmetry

Answer 15

Figure is the same under a rotation, for regular shapes divide 360/#sides for the order of rotational symmetry

Question 16

R o

Answer 16

Point reflection through the origin, (-x,-y)

Question 17

How do you reflect though points other than the origin?

Answer 17

Find the rise and run from the point to the point you are reflecting over and continue the line with that slope so the point you are reflecting over is the midpoint

Question 18

What is a glide reflection?

Answer 18

Composition of a translation and a line reflection, orientation is not preserved

Question 19

A composition of 2…

Answer 19

Translations is a translation

Rotations is a rotation

Question 20

(Don’t have to memorize but good to know) A composition of 2 line reflections through…

Answer 20

Parallel lines is a translation Perpendicular lines is a point reflection
Intersecting lines is a rotation

Question 21

What is Isometry/rigid motion, and an example of not isometric?

Answer 21

Transformations that preserve distance, dilations are the only ones not isometric

Question 22

Direct Isometry

Answer 22

Preserves orientation:
Translations
Rotations
Point reflections

Question 23

Opposite Isometry

Answer 23

Does not preserve orientation:
Line reflections
Glide reflections

Question 24

How do you know if it preserves orientation?

Answer 24

Write out the order of point going clockwise for both figures and see if it’s in the same order e.g. ABCABCABC vs BCABCABCA has preserved orientation