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Interior angles of polygons

Interior angles of polygons. This is just one of the six interior angles of this polygon. The angle sum of a triangle is 180°. A polygon with 3 sides is a triangle. â. ĉ. + + = 180°. What is the angle sum of a quadrilateral?. Angle sum of a triangle = 180°.

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Interior angles of polygons

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  1. Interior angles of polygons This is just one of the six interior angles of this polygon

  2. The angle sum of a triangle is 180° A polygon with 3 sides is a triangle â ĉ + + = 180°

  3. What is the angle sum of a quadrilateral? • Angle sum • of a • triangle • = 180° Angle sum of a triangle = 180° The angle sum of a quadrilateral is 360°

  4. The formula applies for any polygon, not just regular polygons! Here is a different quadrilateral but the method is the same • Angle sum of • a triangle = 180° • Angle sum of • a triangle = 180° The angle sum of a quadrilateral is 360°

  5. What is the angle sum of a pentagon? 3 x 180°= 540° This time you can divide the polygon into 3 triangles • The angle sum of a pentagon is 540°

  6. You can find the angle sum of any polygon by dividing it up into triangles 4 x 180° = 720° • 5 x 180° = 900° 6 x 180° = 1080°

  7. Using the formula (n-2) x 180° Find the angle sum for a dodecagon (a 12-sided polygon) (12-2) x 180°= 10 x 180°= 1800°

  8. EXAMPLES 1) 2) 95° 120° 155° 95° 110° 120° 80° 105° Sum of interior angles = Sum of interior angles = (number of sides – 2) (number of sides – 2) x x 180° 180° ( 5 – 2 ) x ( 6 – 2 ) x Sum of interior angles = Sum of interior angles = 180° 180° Sum of interior angles = Sum of interior angles = x x 3 180° 4 180° Sum of interior angles = Sum of interior angles = 540° 720° Pentagon (5 sides) Hexagon (6 sides) - - - - - - - - - 120° 90° 155° 120° 110° 95° 80° 95° 105°

  9. The sum of interior angles of any polygon 1. Work out the sum of the interior angles of a heptagon 2. Work out the sum of the interior angles of a nonagon (9 sides) 3. Work out the sum of the interior angles of a 14-sided polygon 4. Find the missing angles b) a)

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