The table below shows some information about regular polygons - Junior Cycle Mathematics - Question 14 - 2017

The sum of the interior angles of a polygon with $n$ angles can be found using the formula:

$S = 180(n - 2) \text{ degrees}$

This represents the total sum of the angles in a polygon where $n \geq 3$.

To find the size of each angle in the polygons, we can use the following:

• For a triangle: ( \frac{180°}{3} = 60° )
• For a square: ( \frac{360°}{4} = 90° )
• For a pentagon: ( \frac{540°}{5} = 108° )
• For a hexagon: ( \frac{720°}{6} = 120° )

Thus, the completed table will be:

The size of each interior angle in a regular polygon can be calculated using the formula:

$A = \frac{180(n - 2)}{n} \text{ degrees}$

This gives the measure of each angle when all angles are equal within the polygon, for $n \geq 3$.