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# Angles in a Polygon Examples

### Example 1

 What is the sum of the angles in a dodecagon? A dodecagon has 12 sides, so .

### Example 2

 What is the measure of each angle in a regular nonagon? A nonagon has 9 sides. Using our formula, .

### Example 3

 Find the missing angle. A triangle has 180°. If we add the measures of angles I and J and subtract from 180, we get:

### Example 4

 Find the measurement of angle Q This is a hexagon. The total number of degrees equals:

### Example 5

 Find the missing angles in this isosceles trapezoid. Since this is an isosceles trapezoid, angles I and L are congruent. In addition, angles J and K are congruent, so