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7-50.
1. Jamal used a hinged mirror to create a regular polygon like he did in Lesson 7.1.4. Homework Help ✎

1. If his hinged mirror formed a 72° angle and the core region in front of the mirror was isosceles, how many sides did his polygon have?

2. Now Jamal has decided to create a regular polygon with 9 sides, called a nonagon. If his core region is again isosceles, what angle is formed by his mirror?

$\text{Use the formula: }\frac{360\degree}{\degree \text{of each angle}} = \text{Number of sides}$

5 sides

Use the formula given in hint (a) and solve for the unknown piece.