| --- |
| source: ncert |
| topic: geometry |
| class_level: class_7 |
| chapter: ch10 |
| difficulty: beginner |
| --- |
| |
| Class 7 | Ch10: Practical Geometry |
| Five triangle construction cases: SSS, SAS, ASA, RHS, AAS. |
| SSS: draw base, arc from both ends, intersection=third vertex. |
| SAS: draw base, angle at one end, mark distance on angle ray, join. |
| ASA: draw base (included side), angles at both ends, intersection=third vertex. |
| RHS: right angle, hypotenuse from far end, intersection=right angle vertex. |
| AAS: find third angle (180-sum of two given), then use ASA method. |
| Parallel lines: draw transversal, copy angle at new point. |
| SAS example: PQ=5cm, QR=4.5cm, angle Q=60°. Draw QR=4.5. Angle 60° at Q. Mark P at 5cm. Join PR. |
| SSS example: sides 5,6,7. Draw base 6. Arc radius 5 from one end. Arc radius 7 from other. Intersection=third vertex. |
| Check triangle inequality before constructing. Use sharp pencil. |
