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CHAPTER AT A GLANCE
Constructions and Tilings
•Unit: Geometry
•Board weightage: Constructions with a ruler and a compass (perpendicular bisector, angle bisector, angles of 90, 60, 45, 30 degrees, copying an angle, parallel lines, regular hexagon) and tiling of grids give regular 2-mark, 3-mark and 4-mark questions (please check the latest sample paper)
•Key ideas from the textbook: perpendicular bisector and the proof by congruence, 90 degree angle at a point, angle bisection by SSS, copying an angle, parallel line by equal corresponding angles, 60 degree angle from an equilateral triangle, regular hexagon from six equilateral triangles, angles around a point add to 360 degrees, tiling with 2 × 1 tiles
•Most scoring part: writing every construction step in order with the reason for it (equal radius, equal arcs, congruence condition)
•Time to revise: about 70 minutes
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