CI 515 Definitions of Center by Nicole Rigelman https://padlet.com/rigelman/hyhaopu7vkdk Our definitions of center... discoveries so far. Our looming questions that need further investigation. en-us 2018-08-09 18:29:43 UTC 2026-03-10 11:23:39 UTC hello@padlet.com Shereen, Claudia, and Kelsey https://padlet.com/rigelman/hyhaopu7vkdk/wish/272534853 Definition of center varies depending on the attributes of the shape.

A even number of sides of regular shape- the center can be found by folding midpoint to midpoint or/and vertex to vertex.

Odd number of sides of a regular shape and triangles- the center can be found by folding midpoint to opposite vertex.

Irregular shapes:
Do not follow the these procedures and we don't like them. B/c if it's a quadrilateral, and you fold midpoint to midpoint and vertex to vertex, the meeting points don't match!]]> 2018-08-09 18:41:06 UTC https://padlet.com/rigelman/hyhaopu7vkdk/wish/272534853 Jeremy, Karen, Tamara https://padlet.com/rigelman/hyhaopu7vkdk/wish/272534881 Our definitions so far...
Regular -
*at least 2 lines of symmetry: the point where lines of symmetry intersect (circles are a special case for this because they also have every point equidistant from the center)
*one line of symmetry...?
*no lines of symmetry...?
Do zero and one line(s) of symmetry act the same as each other?
Irregular -
Find the center of gravity by redistributing area equally vertically and horizontally...? 
We tried this out, but we aren't sure if it works :)]]> 2018-08-09 18:41:15 UTC https://padlet.com/rigelman/hyhaopu7vkdk/wish/272534881 Does the center point have anything to do with lines that create equal surface areas? Congruent halves have equal surface area. What about in the case of irregular shapes? https://padlet.com/rigelman/hyhaopu7vkdk/wish/272534945 -Kathleen]]> 2018-08-09 18:41:40 UTC https://padlet.com/rigelman/hyhaopu7vkdk/wish/272534945 Carol, Robyn & Katie https://padlet.com/rigelman/hyhaopu7vkdk/wish/272534955 * for regular polygons the center is equidistant from each of the sides and each of the vertices (although the distance from the center to the side is not equitable to the distance from the center to the vertex)
* Irregular polygons were more fun and folding was easier than constructing with a compass
* Triangles have 4 centers depending on the criteria you use to define them but all 4 centers are the same for equilateral triangles
* Three of the 4 centers of a triangle's center are co-linear]]> 2018-08-09 18:41:42 UTC https://padlet.com/rigelman/hyhaopu7vkdk/wish/272534955 Lyndsay, Hailey, Betty, Wendy hinderhw https://padlet.com/rigelman/hyhaopu7vkdk/wish/272534968 For regular polygons:  the center point is where any two lines of symmetry intersect.

For all all polygons: the functional center is the gravitational center- for regular shapes is the intersecting lines of symmetry center point. ]]> 2018-08-09 18:41:47 UTC https://padlet.com/rigelman/hyhaopu7vkdk/wish/272534968 Jami, Mark, Julie and Alex https://padlet.com/rigelman/hyhaopu7vkdk/wish/272535002 When angles of a regular polygon are bisected, the intersection of the lines created from those  bisections form the center.

For a circle, you can draw a regular polygon within the boundaries of a circle and bisect the angles.  Or you could draw a line touching a single point on the circle and make a 90 degree angle from that point multiple times intersecting at the center.


]]> 2018-08-09 18:42:01 UTC https://padlet.com/rigelman/hyhaopu7vkdk/wish/272535002 Angela, Kathleen, Patty, Celeena https://padlet.com/rigelman/hyhaopu7vkdk/wish/272535026 We know that we can find the center of regular polygons by finding where the lines of symmetry intersect. 
We observe that we cannot find a single equidistant point from all vertices of an irregular polygon, but there is likely a center point of gravity.]]> 2018-08-09 18:42:15 UTC https://padlet.com/rigelman/hyhaopu7vkdk/wish/272535026 Dylan, Nikki, Sabrina, Alla https://padlet.com/rigelman/hyhaopu7vkdk/wish/272535114 If it is a regular polygon it is where at least 2 or more lines of symmetry cross.  
Triangles it is from the vertices to the opposite midpoint where all those lines cross.
Trapezoid (1 line of symmetry) 2 theories: 1 to continue to use the vertices to opposite midpoint and where they meet. 2 to use the regular square to find the midpoint.
We noticed that odd regular shapes you can use vertex to opposite midpoint and even regular shapes you can use lines of symmetry and vertex to vertex.]]> 2018-08-09 18:42:35 UTC https://padlet.com/rigelman/hyhaopu7vkdk/wish/272535114 Lyndsay, Hailey, Betty, Wendy hinderhw https://padlet.com/rigelman/hyhaopu7vkdk/wish/272535682 ?? How do you find that gravitational center of irregular shapes.  


]]> 2018-08-09 18:46:36 UTC https://padlet.com/rigelman/hyhaopu7vkdk/wish/272535682 Two or more "uglier" bisections of a square seem to always go through the center point. They simply need to have congruent halves but don't necessarily symmetrical halves. https://padlet.com/rigelman/hyhaopu7vkdk/wish/272536047 -Kathleen]]> 2018-08-09 18:48:51 UTC https://padlet.com/rigelman/hyhaopu7vkdk/wish/272536047 Center of Gravity Applet https://padlet.com/rigelman/hyhaopu7vkdk/wish/272536935 http://www.physicsclassroom.com/Physics-Interactives/Balance-and-Rotation/COM-Builder/Center-Of-Mass-Interactive]]> 2018-08-09 18:55:12 UTC https://padlet.com/rigelman/hyhaopu7vkdk/wish/272536935 https://padlet.com/rigelman/hyhaopu7vkdk/wish/272537044 2018-08-09 18:56:01 UTC https://padlet.com/rigelman/hyhaopu7vkdk/wish/272537044