a.
\Vertices of
are
and
.
Find reflection along
-axis.
Write the vertex matrix for
is
.
To reflect the in the line
-axis, multiply the vertex matrix by 
.
Write the vertices of the image.
\ The first row represents the
–coordinates and the second row represents the
–coordinates.
The vertices are
and
.
b.
\Graph:
\Plot the points
and
and connect the points to form
.
Plot the points
and
and connect the points to form
.
.gif\")
Observe the graph:
\
and
are similar, both has same shape.
c.
\The points
and
are reflections of the points
and
across
–axis.
is a reflection of
across the
–axis.
d.
\To reflect twice across
–axis, multiply the vertex matrix by the reflection matrix twice.
The reflection matrix for reflection across
–axis is
.
Multiply the reflection matrices are
.
Multiplying a matrix by the identity matrix will give the same matrix.
\Thus, reflecting a triangle twice across the same line will produce the same matrix.
\a. Coordinates of the vertices of the images are
and
.
b.Graph of the
and
is
.gif\")
c.
is a reflection of
across the
–axis.
d. Reflecting a triangle twice across the same line will produce the same matrix.