Presentation on theme: "Exploring Polygons. What are polygons? A polygon is a closed figure made by joining line segments, where each line segment intersects exactly two others."— Presentation transcript:
What are polygons? A polygon is a closed figure made by joining line segments, where each line segment intersects exactly two others. The following are examples of polygons:
The figures below are not polygons. Can you tell why?
Regular Polygons A regular polygon is a polygon whose sides are all the same length, and whose angles are all the same. The following are examples of regular polygons: Would a square be a regular polygon? A rectangle?
The following are not examples of regular polygons: How do you know?
Triangles All three-sided polygons. There are many special types of triangles.
Angles in quadrilaterals… Quadrilaterals have four sides and four angles. The sum of the measures of the angles is 360°. Find the value of x in the quadrilateral below x° + 105° + 80° + 95° = 360° Add 105°, 80°, and 95°. x° + 280° = 360° THINK: What measure added to 280° equals 360°? 80° + 280° = 360° x° = 80°