Question 2 - Figure it out (Page 147) - Constructing Copy of an Angle - Chapter 6 Class 7 - Constructions and Tilings (Ganita Prakash II)

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Question 2 - Figure it out (Page 147) Construct the Fig. 6.6. This procedure to copy an angle finds an important application in constructing parallel lines using only a ruler and compass.We need to recreate the chain of sectors (the "pizza slices") shown in the first image. This requires copying the same angle over and over, but flipping the direction each time. Steps of Construction Draw a straight horizontal line at the top. Mark a point A. Draw an angle (example: 60°) coming down from A. 2. Use your compass to measure a specific length (say 4cm) on both arms. Connect the ends with an arc to make the first 'cone’. 3. Look at the right-side arm of the first unit. The bottom of this arm (Point B) becomes the vertex for the second unit. 4. Copy the original angle at point B, but make sure the new arm goes UP. 5. Measure the same length (4 cm) and draw the arc to close the shape. 6. Now we are at the top again (Point C). The second unit shares its right arm with the third unit. 7. The top of this arm is the new vertex. Construct the angle again, making the new arm go DOWN. 8. Measure the length (4 cm) and close the shape with an arc. 9. Repeat the process. From Point D, copy the angle pointing UP 10. Draw the final arc. We now have 4 units connected in a chain, just like Fig 6.6