Here are some terms and definitions that are important for the SAT geometry section. 

 

Point

A point is a location in space that has no dimension, measurement or mass. It is a spot that exists. They are shown by a dot on a line (*) and are labeled with capital letters like A, B, C and so on. 

 

Line Segment

A line segment is simply the space between two different points. Any two points can make a line and there can be more than two points in a single line. 

 

Ray

A ray is simply a line that extends in one direction infinitely in one direction. It is noted on the exam with a one sided arrow. 

 

Plane

Simply put, a plane is three points in space. There may be more than three points on a plane, but only three need to exist for it to be a plane. When two rays (see above) converge, they create an angle with is noted on the exam by a special symbol followed by three points - one from the vertex (where the rays intersect) and the others the two rays moving outward. 

 

Angels

Measured in degrees, angles are noted by the ° symbol on the exam. A straight angle (a straight line) has a measurement of 180° while vertical angles occur when two different lines intersect to form four triangles.