What do we call the set of all points?
space
What do we call points that lie on the same line?
colinear
Planes that do not intersect are called what kind of planes?
parallel
What is the measure of an angle that is inscribed in a circle?
1/2 of the intercepted arc
What do we call a statement accepted as true without proof?
postulate
Two points in space lie in one and only one ____.
line
What do we call lines that intersect in a single point?
concurrent lines
What do we call set of points in a plane that are a given distance from a point?
circle
What is the formula for finding the circumference of a circle?
c=2pir
What are the 3 undefined terms in the study of plane geometry?
point, line, plane
How many and what kind of points do we need to determine space?
4 noncoplanar points
When two lines intersect, they intersect in one and only one _____________.
point
What results from the intersection of two distinct planes?
line
What is the formula for finding the midpoint of a segment with endpoint coordinates a and b?
m=(a+b)/2
What do we call the union of two distinct rays with a common endpoint?
angle
A point divides a line into three disjoint sets. What are they?
a point and 2 half-lines
What do we call lines that intersect and form an angle measuring 90°?
perpendicular
What is the intersection of a secant plane and a sphere?
circle
How do you find the measure of an angle formed by two secants that intersect in the interior of a circle?
It is half of the sum of the measures of the intercepted arcs.
What do we call the union of three noncollinear points and the line segments connecting them?
triangle