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2. Quadrilaterals

3. Quadrilaterals

4. Quadrilaterals

5. Square
Indicates equal sides
Box indicates 900 angle

6. Indicates equal sides
Box indicates 900 angle

7. Indicates equal sides

8. Indicates equal sides

12. An interior angle (or internal angle) is an angle
formed by two sides of a simple polygon that share
an endpoint.
Interior angles of a quadrilateral always equal
360 degrees.