- In geometry a quadrilateral is a four-sided polygon, having four edges (sides) and four corners (vertices). The word is derived from the Latin words quadri, a variant of four, and latus, meaning “side”. It is also called a tetragon, derived from greek “tetra” meaning “four” and “gon” meaning “corner” or “angle”, in analogy to other polygons (e.g. pentagon). Since “gon” means “angle”, it is analogously called a quadrangle, or 4-angle. A quadrilateral with vertices A, B, C and D is sometimes denoted as ABCD.
- Marymoor Park (Wikipedia)
Marymoor Park, located on the north end of Lake Sammamish in Redmond, Washington, is King County’s largest, oldest, and most popular park, with more than 3 million annual visitors coming to roam its 640 acres (2.6 km2). Among recreational activities available are various sports facilities, rock climbing, a 40-acre off-leash dog park and a velodrome. It is also one end of the Sammamish River Trail, a biking and walking trail. In addition, a radio control aircraft flying field and a pet memorial garden are within the park’s boundaries.