📐 Part 1: Understanding Scale Factors

1. Circle the correct definition of a scale factor:

The number we multiply all side lengths by to resize a shape

The number we add to all side lengths to make a shape bigger

The number of angles in a shape

The perimeter of the original shape

2. If a rectangle has a length of 8cm and we resize it using a scale factor of 3, what is the new length?

3. If a triangle has a side length of 12cm and we resize it using a scale factor of 1/4, what is the new side length?

🔄 Part 2: Properties That Change and Stay the Same

4. When we resize a 2D shape, tick ALL the properties that stay the same (invariant properties):

Angle measures

Side lengths

Shape of the figure

Perimeter

Orientation (which way it faces)

Area

5. Fill in the blanks:

When we resize a shape, the __________ stay the same but the __________ change. This means the shape looks exactly the same but is either __________ or __________.

📏 Part 3: Calculating New Dimensions

6. A square has sides of 6cm. Complete the table showing the new side lengths for different scale factors:

Original side length: 6cm

Scale factor 2: New side length = _______ cm

Scale factor 1/2: New side length = _______ cm

Scale factor 4: New side length = _______ cm

Scale factor 1/3: New side length = _______ cm

7. A parallelogram has sides of 10cm and 15cm. If we resize it using a scale factor of 1/5, calculate the new dimensions:

8. Match each scale factor with what happens to the shape:

1. Scale factor = 3

2. Scale factor = 1/2

3. Scale factor = 1

4. Scale factor = 5

A. Shape becomes half the size

B. Shape stays exactly the same size

C. Shape becomes 5 times bigger

D. Shape becomes 3 times bigger

🎨 Part 4: Drawing Resized Shapes

9. On the grid below, draw a triangle that has been resized by a scale factor of 2. Show your measurements:

10. Draw a rectangle with dimensions 4cm × 6cm, then draw it resized by a scale factor of 1/2:

🏗️ Part 5: Composite Shapes

11. A composite shape is made from a rectangle (8cm × 4cm) with a triangle (base 4cm, height 3cm) on top. If we resize this composite shape by a scale factor of 3, what are the new dimensions?

Rectangle: Length = _______ cm, Width = _______ cm

Triangle: Base = _______ cm, Height = _______ cm

12. Explain in your own words why all parts of a composite shape must be resized by the same scale factor:

🧠 Part 6: Problem Solving

13. Sarah wants to make a model kite that is 1/3 the size of the original. If the original kite has dimensions of 60cm × 45cm, what will be the dimensions of her model?

14. True or False? Circle your answers:

True

False: When scale factor is greater than 1, the shape gets smaller

True

False: When scale factor is a unit fraction, the shape gets smaller

True

False: A scale factor of 1 means the shape doesn't change size

True

False: The angles in a shape change when we resize it

15. Challenge: If a shape is resized by a scale factor of 2, and then resized again by a scale factor of 1/4, what is the overall effect on the original shape?