Unit 1- Lesson 5 - Grade 8: Illustrative Mathematics

Select all of the translations that take Triangle T to Triangle U. There may be more than one correct answer.

• A. Translate (-3, 0) to (1, 2) .
• B. Translate (2, 1) to (-2, -1) .
• C. Translate (-4, -3) to (0, -1) .
• D. Translate (1, 2) to (2, 1) .

If the point (13, 10) were reflected using the X-axis as the line of reflection, what would be the coordinates of the image? What about (13, -20)? (13, 570)? Explain how you know.

Without graphing, predict the coordinates of the image of point R if point R were reflected using the y-axis as the line of reflection.

What are the coordinates of R'?

Suppose you reflect a point using the y-axis as line of reflection. How would you describe its image?

Rotate segment AB 90 degrees counterclockwise around center B. Label the image of A as C. What are the coordinates of C?

Rotate segment AB 90 degrees counterclockwise around center A. Label the image of B as D. What are the coordinates of D?

Compare the two 90-degree counterclockwise rotations of segment AB. What is the same about the images of these rotations? What is different?

Identify the center of rotation. And label the rotated image PQR.

Identify the line of reflection. And label the reflected image XYZ.