# Transformations

> Grade 8: reflection in a line, rotation about a point, translation by a vector, enlargement and scale factor, congruent and similar shapes.

Source: https://olyclass.com/library/math-g8-transformations-en/

- Subject: Math
- Level: Grade 8
- Practice: 16
- Play it free on one screen (projector, TV or whiteboard): https://olyclass.com/library?play=math-g8-transformations-en
- Copy and edit it: https://olyclass.com/library?copy=math-g8-transformations-en
- Games it plays well in: [Ladder Climb](https://olyclass.com/classroom-games/ladder-climb/), [Paper Race](https://olyclass.com/classroom-games/paper-race/), [Three in a Row](https://olyclass.com/classroom-games/three-in-a-row/), [Line of Four](https://olyclass.com/classroom-games/line-of-four/)

## Questions

1. When a point is reflected in the y-axis, which coordinate changes sign? (Both coordinates / Neither coordinate / The x-coordinate / The y-coordinate)
   Answer: The x-coordinate
2. The point (2, 3) is reflected in the vertical line x = 4. Where is its image? ((-2, 3) / (2, 5) / (3, 6) / (6, 3))
   Answer: (6, 3)
3. When a shape is reflected in a mirror line, its image is the same size as the original.
   Answer: True
4. Which statement is true for any point and its image in a reflection? (Both are the same distance from the mirror line / The image always lies on the mirror line / The image is closer to the mirror line / The image is twice as far from the mirror line)
   Answer: Both are the same distance from the mirror line
5. Which turn about a point is the same as a half turn? (180° / 270° / 360° / 90°)
   Answer: 180°
6. Point (3, 1) is rotated 90° anticlockwise about the origin (0, 0). Where does it land?
   Answer: (-1, 3)
7. The centre of rotation is the one point that does not move.
   Answer: True
8. Translate the point (1, 2) by the vector (3, -4), where 3 is right and -4 is down. Result? ((-2, 4) / (-3, 6) / (4, -2) / (4, 6))
   Answer: (4, -2)
9. A translation moves (5, 5) to (2, 9). What is the vector?
   Answer: (-3, 4)
10. A rectangle 2 cm by 3 cm is enlarged by scale factor 4. What are its new sides? (4 cm by 6 cm / 6 cm by 7 cm / 8 cm by 12 cm / 8 cm by 3 cm)
   Answer: 8 cm by 12 cm
11. An enlargement with a positive scale factor makes the image smaller. The scale factor is… (between 0 and 1 / exactly 1 / greater than 1 / less than 0)
   Answer: between 0 and 1
12. After an enlargement with scale factor 3, every angle in the shape is multiplied by 3.
   Answer: False
13. A line of length 15 cm is the image after enlarging by scale factor 5. What was the original length? (10 cm / 20 cm / 3 cm / 75 cm)
   Answer: 3 cm
14. Which transformation can change the size of a shape? (Enlargement / Reflection / Rotation / Translation)
   Answer: Enlargement
15. Two shapes are exactly the same shape and size. What word describes them?
   Answer: Congruent
16. Two similar triangles: a 4 cm side in the smaller matches 10 cm in the larger. Scale factor? (0.4 / 1.5 / 2.5 / 6)
   Answer: 2.5