The big picture
Here is the whole track on one page.
| Idea | Remember | Example |
|---|---|---|
| Exact, not neat | A construction passes its check. A drawing by eye may not. | Sides 40, 40, 40, 42 mm: one is off. |
| The circle | Every point is one radius from the centre. | An oval fails. A compass ring passes. |
| Across the middle | The diameter is the radius twice over. | Radius 30 mm gives diameter 60 mm. |
| Carrying a length | The compass span holds a length. No number is read. | An arc from C copies AB. |
| Square corners | Equal marks on both arms. Measure the gap. | 30 mm marks leave a gap of 42 mm. |
| Steps in order | A step needs what it uses to be there first. | A shut compass cannot swing an arc. |
Open your book to Chapter 8, Playing with Constructions. You have already done each of these.