Name Date
Class
Lesson Congruent Figures
Reteach
9-5
When combining the transformations below, the original figure and
transformed figure are congruent. Even though the size does not
change, the orientation of the figure might change.
Transformation
Algebraic Coordinate Mapping
Orientation
Translation
(x, y) → (x + a, y+b) translates left or right a units
and up or down b units
same
Reflection
(x, y) →(-x, y) reflects across the y-axis
different
(x, y) = (x-) reflects across the x-axis
(x, y) → (-x-y) rotates 180° around origin
Rotation
(x, y) →y. -x) rotates 90° clockwise around origin
different
(x, y) + (-y, x) rotates 90° counterclockwise around
origin
1st transformation: translation right 4 units
(x, y) + (x+4,7). orientations same
2nd transformation: reflection over the x-axis
(x, y) → (x-y). orientation: different
3rd transformation: rotation 90° clockwise
(x, y) → (y, -x) orientation different
Describe each transformation. Express each algebraically.
Tell whether the orientation is the same or different.
1. First transformation
Description:
Algebraically
Orientation:
20
2
2
2. Second transformation
Description:
Algebraically
Orientation