standard_description: Verify experimentally the properties of dilations given by a center and a scale factor:
- A dilation takes a line not passing through the center of the dilation to a parallel line, and leaves a line passing through the center unchanged.
- The dilation of a line segment is longer or shorter in the ratio given by the scale factor.
problem_activity: Task
Below is a picture of a triangle on a coordinate grid:
[IMG]
Draw the reflection of $\triangle ABC$ over the line $x = -2$. Label
the image of $A$ as $A^\prime$, the image of $B$ as  $B^\prime$ and
the image of $C$ as $C^\prime$.
Draw the reflection of $\triangle A^{\prime}B^{\prime}C^\prime$ over the line $x = 2$. Label
the image of $A^\prime $ as $A^{\prime \prime}$, the image of $B^\prime$ as  $B^{\prime \prime}$ and
the image of $C^\prime$ as $C^{\prime \prime}$.
What single rigid transformation of the plane will map $\triangle ABC$ to
$\triangle A^{\prime \prime}B^{\prime \prime}C^{\prime \prime}$?  Explain.


aligns: no