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Angles, Polygons and Bearings

<h3>Angles in polygons</h3><p>A <strong>polygon</strong> is a closed figure with straight sides. The sum of its <strong>interior angles</strong> is <code>(n - 2) x 180°</code> where n is the number of sides. The sum of <strong>exterior angles</strong> of any polygon is always <code>360°</code>. For a regular polygon, each exterior angle is <code>360° ÷ n</code>.</p><h3>Bearings</h3><p>A <strong>bearing</strong> is a direction measured clockwise from north, written with three figures, such as 045° or 270°. Due east is 090°, due south is 180°, and due west is 270°.</p><div class="callout"><strong>Kenyan context:</strong> A hiker leaves a camp and walks on a bearing of 060° towards a hill, then turns to a bearing of 150° to reach a river. A regular hexagonal floor tile (6 sides) has interior angles summing to <code>(6 - 2) x 180° = 720°</code>, so each angle is <code>720° ÷ 6 = 120°</code>.</div>
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The interior angles of a triangle add up to: