Term
|
Definition
|
A point specifies only location; it has no length, width, or depth. We usually represent a point with a dot on paper, but the dot we make has some dimension, while a true point has dimension
|
|
[image]
|
|
|
|
Term
|
Definition
| A line has only one dimension: length. It continues forever in two directions (so it has infinite length), but it has no width at all. A line connects two points via the shortest path, and then continues on in both directions. |
|
|
Term
|
Definition
| A line segment is the portion of a line lying strictly between two points. It has a finite length and no width. |
|
|
Term
|
Definition
|
ray can be thought of as a half a line. It has a point on one end, and it extends infinitely in the other direction.
|
| |
|
|
|
Term
|
Definition
|
A plane is a flat, two-dimensional object. We often represent a plane by a piece of paper, a blackboard, or the top of a desk. In fact, none of these is actually a plane, because a plane must continue infinitely in all directions and have no thickness at all. A plane can be defined by two intersecting lines or by three non-collinear points.
|
|
[image]
|
| [image] |
| |
|
|
|
Term
|
Definition
- Three or more points that lie on the same straight line are called to be Collinear.
[image] |
|
|
Term
|
Definition
wo objects are coplanar if they both lie in the same plane. In the figure above, the two rectangles ABCD and PQRS are both coplanar.
[image] |
|
|
Term
|
Definition
Angles are formed by two rays that begin at the
same point or share the same endpoint.
[image]
|
|
|
Term
|
Definition
Midpoint of a line segment is the point that is halfway between the endpoints of the line segment.
[image] |
|
|
Term
|
Definition
Angle Bisector is a ray that divides an angle into two equal parts.
[image] |
|
|
Term
|
Definition
Two figures are congruent if all corresponding lengths are the same, and if all corresponding angles have the same measure. Colloquially, we say they "are the same size and shape," though they may have different orientation. (One might be rotated or flipped compared to the other.)
[image] |
|
|
Term
|
Definition
[image]
|
close window
|
|
A vertex is the point where two sides of a polygon meet.
|
| |
|
|
|
Term
|
Definition
The measure of an angle with a measure between 0° and 90° or with less than 90° radians.
[image]
|
|
|
Term
|
Definition
Angle measures greater than 90 degrees but less than 180 degrees.
[image]
|
|
|
Term
|
Definition
A right angle measures exactly 90 degrees. (Remember the uppercase letter L which will help you remember the angle of a right angle)
[image]
|
|
|
Term
|
Definition
Straight Angles measure exactly 180 degrees
[image]
|
|
|
Term
|
Definition
[image]
|
The two angles involved when the sum is 90°.
|
|
|
|
Term
|
Definition
Two Angles are Supplementary if they add up to 180 degrees.
They don't have to be together to be supplementary, just so long as the total is 180 degrees.
[image]
|
|
|
Term
|
Definition
Vertical Angles are the angles opposite each other when two lines cross.
[image] |
|
|
Term
|
Definition
Either of two angles having a common side and a common vertex.
[image] |
|
|
Term
|
Definition
Linear Pair is a pair of adjacent angles that form a straight line.
[image] |
|
|
Term
|
Definition
Polygons are 2-dimensional shapes. They are made of straight lines, and the shape is "closed" (all the lines connect up).
[image] |
|
|
Term
|
Definition
A quadrilateral is a 2-dimensional closed shape with four straight sides. E.g. The shape ABCD shown here is a quadrilatera
[image] |
|
|
Term
|
Definition
Pentagon is a polygon with five sides
[image] |
|
|
Term
|
Definition
a hexagon is a polygon with six edges and six vertices.
[image] |
|
|
Term
|
Definition
A polygon with eight sides is called an octagon
[image] |
|
|
Term
|
Definition
Decagon is a polygon with 10 sides and equal number of angles.
[image] |
|
|
Term
|
Definition
A 12-sided polygon (a flat shape with straight sides).
[image] |
|
|
Term
|
Definition
A polygon with n sides. For example, an 8-gon is another name for an octagon.
|
|
|
Term
|
Definition
polygon with one or more interior angles greater than 180°. It looks sort of like a vertex has been 'pushed in' towards the inside of the polygon.
[image] |
|
|
Term
|
Definition
|
|
Term
|
Definition
A polygon whose sides are not all the same length or whose interior angles do not all have the same measure.
[image] |
|
|
Term
|
Definition
olygon that has all sides equal and all interior angles equal
[image] |
|
|
Term
|
Definition
Diagonal is a line segment connecting two non-adjacent vertices of a polygon.
[image] |
|
|
Term
|
Definition
A side of a polygon is a line segment connecting any two vertices of the polygon. edge
[image] |
|
|
Term
|
Definition
he distance around a two-dimensional shape.
[image] |
|
|
