Dilations with Different Scale Factors
About This Diagram
This diagram shows how dilations change the size of a figure while preserving its shape. Click different scale factors to see enlargements and reductions.
Scale Factor Effects
| Scale Factor | Effect | Example |
|---|---|---|
| k > 1 | Enlargement | k = 2 doubles size |
| k = 1 | No change | Identity |
| 0 < k < 1 | Reduction | k = 0.5 halves size |
Visual Elements
- Red dot: Center of dilation
- Blue triangle: Pre-image
- Green triangle: Image (dilated)
- Dashed lines: Radial lines from center through vertices
- Distance labels: Show proportional changes
Key Concepts
- All points move along lines through the center
- Distances are multiplied by scale factor k
- Shape is preserved, but size changes
- Dilations are NOT rigid motions!
Coordinate Rule
(x, y) → (kx, ky) when center is at origin
Interaction
Click "k = 2", "k = 0.5", or "k = 1.5" to animate each dilation.
Learning Objectives
- Understand how scale factor affects size
- Apply dilation rules to coordinates
Bloom's Taxonomy Level
Understanding and Applying - Visualizing dilations.
Iframe Embed Code
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