Name: _______________________________________ Date: _______________________

M8-U3: Notes #2 – Reflections Class: _______________________

A reflection is a transformation which ____________ the figure over a ________________________.

This line is called the .

Example 1:
ΔABC is being reflected over the x-axis.

Draw and label the image ΔA’B’C’.

We can use an arrow to describe this reflection.

ΔABC ΔA’B’C’

What are the coordinates of:

A ________ A’ _________

B ________ B’ _________

C ________ C’__________

Write a general rule for an x-axis reflection:

(x, y) ( ________ , _______ ).

Tell me more about this figure, is it congruent or similar? Explain how you know.

Example 2:
ΔABC is reflected over the y-axis.

Draw the image ΔA’B’C’.

What are the coordinates of:

A ________ A’ _________

B ________ B’ _________

C ________ C’ __________

Write a general rule for a y-axis reflection:

(x, y) ( ________ , _______ ).

Example 3:

a) Draw ΔJKL which has coordinates J (0,2), K (3,4), and L (5,1).
b) Draw the image ΔJ’K’L’ after a reflection of ΔJKL over the x-axis.
c) List the coordinates of J’K’L’. J (0, 2) J’ _________

K (3, 4) K’ _________

L (5, 1) L’__________

d) Draw the image ΔJ’’K’’L’’ after a reflection of ΔJ’K’L’ over the y-axis.

e) List the coordinates of J’’K’’L’’.
J’_________ J’’ _________

K’_________ K’’ _________

L’_________ L’’__________

f) Describe a different combination of two reflections that would move ΔJKL to ΔJ’’K’’L’’.

g) Is this new image congruent or similar to the original figure?

Example 4:

a) Draw ΔABC which has coordinates A(0,1), B(3,4), and C(5,1).

b) Draw the image ΔA’B’C’ after a reflection of ΔABC over x = -1.

c) List the coordinates of A’B’C’.

A (0, 1) A’ _________

B (3, 4) B’ _________

C (5, 1) C’__________

Example 5:

a) Draw ΔABC which has coordinates A(0,1), B(3,4), and C(5,1).
b) Draw the image ΔA’B’C’ after a reflection of ΔABC over y = -2.

c) List the coordinates of A’B’C’.

A (0, 1) A’ _________

B (3, 4) B’ _________

C (5, 1) C’__________

Example 6:

Draw the line of reflection which caused rectangle KLMN to reflect onto rectangle K’L’M’N’. What is the equation of the line of reflection?

Example 7:

Draw the line of reflection which caused triangle ABC to reflect onto triangle A’B’C’. What is the equation of the line of reflection?

Example 8:
Quadrilateral CDEF is plotted on the grid below.

On the graph, draw the reflection of polygon CDEF over the x-axis. Label the image C’D’E’F’.

Now create polygon C”D”E”F” by translating polygon C’D’E’F’ three units to the left and up two units. What will be the coordinates of point C”?

Answer ______________

Example 9:
Describe how you could move shape 2 to exactly match shape 2’ by using one translation and one reflection.