Transformations

Reflections

Example Reflect ABCD in the given mirror line

Mirror line

A

B

D

C

Example Reflect triangle PQR in the given mirror line

Mirror line

P

Q

R

Example Reflect triangle LMN in the given mirror line

Mirror line

L

M

M

Example Reflect the rectangle in the given mirror line

Mirror line

Example Reflect the trapezium in the given mirror line

Mirror line

–5 –4 –3 –2 –1 0 1 2 3 4 5 x

y

1

2

3

4

–1

–2

–3

–4

–5

Example Reflect triangle ABC in the x axisA

C B

Example Reflect triangle DEF in the y axis

–5 –4 –3 –2 –1 0 1 2 3 4 5 x

y

1

2

3

4

–1

–2

–3

–4

–5

E

F

D

Example Reflect triangle GHK in the line x = 1

–5 –4 –3 –2 –1 0 1 2 3 4 5 x

y

1

2

3

4

–1

–2

–3

–4

–5

H

G K

Example Reflect triangle LMN in the line2y

–5 –4 –3 –2 –1 0 1 2 3 4 5 x

y

1

2

3

4

–1

–2

–3

–4

–5 L

M

N

Example Reflect triangle PQR in the linexy

–5 –4 –3 –2 –1 0 1 2 3 4 5 x

y

1

2

3

4

–1

–2

–3

–4

–5

P R

Q

Example

Given ABC with A(1, 3) B(1, 5) and C(4, 5), obtain the

image under the following transformations in each

case.

a) Reflection in

b) Reflection in

c) Reflection in

d) Reflection in

–5 –4 –3 –2 –1 0 1 2 3 4 5 x

y

1

2

3

4

–1

–2

–3

–4

–5

B

A

C

Example

Given ABC with A(1, 3) B(1, 5) and C(4, 5), obtain the image under the following transformations in each case.

a) Reflection in

b) Reflection in

c) Reflection in

d) Reflection in .

ExampleComplete the object below so that it has the given two lines of symmetry.