# Lesson 6: Describing Transformations

Let’s transform some polygons in the coordinate plane.

## 6.1: Finding a Center of Rotation

Andre performs a 90-degree counterclockwise rotation of Polygon P and gets Polygon P’, but he does not say what the center of the rotation is. Can you find the center?

## 6.2: Info Gap: Transformation Information

Your teacher will give you either a problem card or a data card. Do not show or read your card to your partner.

If your teacher gives you the problem card:

3. Explain to your partner how you are using the information to solve the problem.

If your teacher gives you the data card:

2. Ask your partner “What specific information do you need?” and wait for your partner to ask for information. Only give information that is on your card. (Do not figure out anything for your partner!)
3. Before telling your partner the information, ask “Why do you need that information?”
4. After your partner solves the problem, ask them to explain their reasoning and listen to their explanation.

When we perform a sequence of transformations, the order of the transformations can be important. Here is triangle $ABC$ translated up two units and then reflected over the $x$-axis.
Here is triangle $ABC$ reflected over the $x$-axis and then translated up two units.
Triangle $ABC$ ends up in different places when the transformations are applied in the opposite order!