Always, Sometimes, or Never
Two lines that do not intersect are parallel.
Always
Two rays with the same endpoint form an angle.
FACT
The line at which two planes intersect
(Show someone an example in the room and see if they agree.)
Point B is between A and C. Segment AC is 20 and BC is 4, find AB.
16
A location in space is the definition of a...
point
If Point B is between points A and C, AB is congruent to BC.
Sometimes (only if B is the midpoint)
If two angles form a straight angle, they are complementary.
FICTION
Two parallel lines
(Show someone an example in the room and see if they agree.)
Ray BC bisects angle ABD. Angle ABD is 80 degrees, so what is angle ABC?
40 degrees
If B is between points A and C, AB + BC = AC. Name the postulate that tells us this is true.
The Segment Addition Postulate
Two lines intersect at a point.
Always
If points A and B lie in plane P, then so does any point of ray AB.
FACT
Three pairs of parallel planes.
(Show someone an example in the room and see if they agree.)
Segment RS and Segment CD bisect each other. They also intersect at point O. Name all of the congruent pieces.
RO is congruent to OS. CO is congruent to OD.
Define a ray.
A ray starts at a point but continues forever.
There are only two points on a line.
Never
If angle ABC + angle CBD = angle ABD, then point C is on the interior of angle ABD.
FACT
Two lines that intersect in the same plane.
(Show someone an example in the room and see if they agree.)
The ledge of a whiteboard is parallel to the cork board strip at the top of the whiteboard. What is the plane that contains both lines.
The whiteboard
True or False: If O, N, and P are collinear, they are coplanar.
True
A bisector of a line segment creates two supplementary angles
Always
Two intersecting lines are coplanar.
FACT
Three planes intersecting.
(Show someone an example in the room and see if they agree.)
D is the midpoint between point X and point Y. If segment DX=4x+3 and XY=3x+10. Find x.
x=4/5
An angle is double its complement. Find the angle
60