Constructions and Tilings | FIO

Question 14

Construct the Fig. 6.6.

Question diagram 1
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Solution

The figure is made of sectors of circles. All sectors have the same radius and a 60-degree central angle.

Step 1 — Choose radius and first segment

Let us choose a suitable radius. Let us call it r. Draw a line segment. Let its length be r. Let us name its endpoints V1V_1 and V2V_2.

Diagram 1

Step 2 — Construct the first shaded sector

We will make an equilateral triangle V0V1V2V_0V_1V_2. Place the compass point at V1V_1. Open the compass to radius r. Draw an arc above V1V2V_1V_2. Place the compass point at V2V_2. Open the compass to radius r. Draw another arc above V1V2V_1V_2. The arcs meet at point V0V_0. Join V0V_0 to V1V_1 with a straight line. Join V0V_0 to V2V_2 with a straight line. Place the compass point at V0V_0. Open the compass to radius r. Draw an arc connecting V1V_1 and V2V_2. This forms the first shaded sector.

Diagram 2

Step 3 — Construct the first unshaded sector

We will make an equilateral triangle V1V2V3V_1V_2V_3. Place the compass point at V1V_1. Open the compass to radius r. Draw an arc below V1V2V_1V_2. Place the compass point at V2V_2. Open the compass to radius r. Draw another arc below V1V2V_1V_2. The arcs meet at point V3V_3. Join V2V_2 to V3V_3 with a straight line. Join V1V_1 to V3V_3 with a straight line. Place the compass point at V2V_2. Open the compass to radius r. Draw an arc connecting V1V_1 and V3V_3. This forms the first unshaded sector.

Diagram 3

Step 4 — Construct the second shaded sector

We will make an equilateral triangle V2V3V4V_2V_3V_4. Place the compass point at V2V_2. Open the compass to radius r. Draw an arc above V2V3V_2V_3. Place the compass point at V3V_3. Open the compass to radius r. Draw another arc above V2V3V_2V_3. The arcs meet at point V4V_4. Join V3V_3 to V4V_4 with a straight line. Join V2V_2 to V4V_4 with a straight line. Place the compass point at V3V_3. Open the compass to radius r. Draw an arc connecting V2V_2 and V4V_4. This forms the second shaded sector.

Diagram 4

Step 5 — Construct the second unshaded sector

We will make an equilateral triangle V3V4V5V_3V_4V_5. Place the compass point at V3V_3. Open the compass to radius r. Draw an arc below V3V4V_3V_4. Place the compass point at V4V_4. Open the compass to radius r. Draw another arc below V3V4V_3V_4. The arcs meet at point V5V_5. Join V4V_4 to V5V_5 with a straight line. Join V3V_3 to V5V_5 with a straight line. Place the compass point at V4V_4. Open the compass to radius r. Draw an arc connecting V3V_3 and V5V_5. This forms the second unshaded sector.

Diagram 5

Step 6 — Construct the third shaded sector

We will make an equilateral triangle V4V5V6V_4V_5V_6. Place the compass point at V4V_4. Open the compass to radius r. Draw an arc above V4V5V_4V_5. Place the compass point at V5V_5. Open the compass to radius r. Draw another arc above V4V5V_4V_5. The arcs meet at point V6V_6. Join V5V_5 to V6V_6 with a straight line. Join V4V_4 to V6V_6 with a straight line. Place the compass point at V5V_5. Open the compass to radius r. Draw an arc connecting V4V_4 and V6V_6. This forms the third shaded sector.

Diagram 6

Step 7 — Shade the regions

Shade the first, third, and fifth sectors. These are the sectors V0V1V2V_0V_1V_2, V3V2V4V_3V_2V_4, and V5V4V6V_5V_4V_6. The final figure is now constructed.

Diagram 7

More questions in FIO

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