Geometry in Our World <ul><li>By Lola, Gillian, and Grace </li></ul>
Two Lines Are Coplanar: Sometimes The guitar neck represents a plane. The strings represent lines on that plane. This is an example of when this statement is true. This highway intersection represent two planes. One line is on each plane showing that two lines are not always coplanar.
A Line Intersects a Plane in One Point: Sometimes The pencil (line) is going through the paper (plane). They intersect in a single point. The road shows a line that intersects a plane at infinite points, or in a line.
Two Planes Intersect in a Line: Sometimes The sides of the fence each represent one plane and they intersect in a line at the corner of the fence. These two shelves represent two parallel planes. Because they are parallel they will never intersect.
Two Planes Intersect in a Single Point: Never Because two planes go on forever, they are infinite which means that if they intersect, they will always intersect in infinite points, or a line.Three planes can intersect in a point, because there is only one point that they all would intersect, but every plane would intersect with one of the others in a line.
Planes Have an Edge: Never Planes don’t have edges because they go on infinitely. Planes are only drawn with edges so that they are easier to visualize.
Two Points Are Collinear: Always The two birds each represent a point on the line (wire). You can always draw a line between any two points no matter where they are placed on a plane.
Three Point Are Collinear: Sometimes Orion’s Belt shows three points, the stars, all in a line. You can’t draw a line through all three stones, or points, on this plane, or beach. Therefore they are not collinear.
Three Points Are Coplanar: Always The three raindrops, points, are all on the window or plane. No matter where any three points are placed you can always angle a plane to make all three coplanar.
Sometimes all four of the horses hooves, or points, are on the ground, or plane. Therefore they are coplanar. Four Points are Coplanar: Sometimes This horse is rearing and two of his hooves are not on the ground. Therefore all four of his hooves are not coplanar.
A Point is a Small, Filled Circle THIS IS NOT A POINT! A point has zero dimensions, and is actually invisible. A very small filled circle is used to represent a point because people can’t draw something with zero dimensions. A small filled circle has two dimensions, therefore can not be a real point.