Spatial+Thinking

Point- An exact location or location on a plane surface

**__ Line- __** A straight path connecting two points and extending endlessly beyond the points in both directions

**__Plane-__** A two-dimensional flat surface that extends endlessly in all directions

**__Line Segment-__** All points between two given points; a fragment of a line. **__Ray-__** A line with a point on one end that goes on endlessly in the other direction.

__**Parallel lines-**__ Two distinct coplaner lines that do not intersect. They have the same slope but different y-intersects.


 * __Skew Lines-__** Two nonparallel lines in space that do not intersect and are not parallel

**__Vertical Angles-__** Angles opposite one another at the intersection of two lines
 * __Adjacent Angles-__** Two angles in a plane which share a common vertex and a common side but do not overlap.


 * __ Congruent Angles- __** Congruent angles have the exact same measure.

**__Supplementary Angles-__** Any two angles that add up to 180 degrees


 * __ Complementary Angles- __** Two acute angles that add up to 90 degrees

**__Transversal-__** A line that cuts across a set of linesof a plane figure. Transversals often cut across parallel lines.
 * __ Corresponding Angles- __**

**__Alternate Interior Angles-__** Two congruent interior angles that lie on different parallel lines and opposite sides of a transversal. **__Regular Polygon-__** A polygon which has all sides and angles mutulally congruent.
 * __Polygon-__** A closed plane figure for which all sides are line segments. The name of a polygon describes the number of sides. A polygon which has all sides and angles mutually congruent is called a regular polygon.

__**Circle-**__ The set of all points that are the same distance from a given point, the center of the circle. __**Central Angle-**__ An angle in a circle with the vertex at the circle's center.

**__Perpendicular Lines-__** Lines that intersect at a 90 degree angle. Perpendicular lines have slopes that are negative reciprocals. **__Segment Bisector-__** A line segment or ray that divides a segment into two congruent segments.

**__Perpendicular Bisector-__** The line perpendicular to a segment passing through the segment's midpoint.

**__Angle Bisector-__** A ray that divides an angle into two congruent angles.


 * __Transformation-__** A change of position or size of a figure

**__Translation-__** A transformation that moves points the same distance and in the same direction

__**Image-**__ The figure you get after a transformation

**__Reflectional Symmetry-__** When one half of a figure is a mirror image of the other half. __**Line of Symmetry-**__ The line that divides a figure with reflectional symmetry into two congruent paths. __**Reflection-**__ Flips a figure over a line of reflection

__**Line of Reflection-**__ Any line across which a figure is reflected

**__Rotation-__** a transformation that turns a figure about a fixed point

__**Center of Rotation-**__ In a rotation the point that does not move. The rest of the plane rotates around this one fixed point.

__**Angle of Rotation-**__ The angle measure of rotation. __**Rotational Symmetry-**__ A figure that can rotate 180 degrees or less so that its image matches the original figure