Geometry

angle addition postulate

If B is in the interior of ?AOC, then m?AOB + m?BOC = m?AOC

adjacent angles

Two angles are (blank) if they share a common vertex and side, but have no common interior points

angle

a (blank) consists of two different rays that have the same initial point. The rays are the sides of the (blank) and the initial point is the vertex of the (blank)

subtraction POE

If a=b, then a-c = b-c

obtuse angle

an angle with a measure greater than 90� and less than 180�

congruent segments

two segments are (blank) if they have the same length

segment bisector

a segment, ray, line, or plane that intersects a segment at its midpoint

division POE

If a=b and c?0, then a�0 = b�0

interior of an angle

every nonstriaght angle has an (blank). point D is in the (blank) of ?A if it is between points that lie on each side of the angle

Through any two distinct points...

...there exists exactly one line.

opposite rays

on the line AB, if C is between A and B, then CA-> and CB-> are (blank)

transitive POC

if one geometric object is congruent to a second, and the second is congruent to a third, then the first object is congruent to the third object.

straight angle

an angle with a measure of 180�

acute angle

an angle with a measure greater than 0� and less than 90�

symmetric POC

If one geometric object is congruent to a second, then the second object is congruent to the first.

Through any three non collinear points...

...there exists only one plane.

If two distinct points lie in a plane...

...then the line containing them lies in the plane.

exterior of an angle

Every non straight angle has a (blank). Point D is in the (blank) of ?A if it is not on sides of the angle or in the interior of the angle

multiplication POE

If a=b, then ac=bc

A line is perpendicular to a plane...

...if it is perpendicular to each line in the plane that intersects it.

right angle

an angle with a measure of 90�

reflexive POE

for any real number a, a=a

angle bisector

a ray that divides the angle into two congruent angles

line segment

AB, or (line above) AB, consists of the endpoints A and B and all points on (line with arrows above)AB that lie between A and B

transitive POE

If a=b and b=c, then a=c

midpoint of a segment

the point that divides the segment into two congruent segments

symmetric POE

If a=b, then b=a

addition POE

If a=b, then a+c = b+c

perpendicular lines

two lines are (blank) if they intersect to form a right angle

a line contains...

... at least two points.

reflexive POC

any geometric object is congruent to itself

a plane contains at least...

...three noncollinear points

if two distinct planes intersect...

...then their intersection is a line

collinear

points, segments, or rays that are on the same line

ray

ray AB, or (line with one arrow head to the right) AB, consists of the initial point A and all points on (line with two arrow heads) AB that lie on the same side of A as B lies

segment addition postulate

If B is between A and C, then AB + BC = AC

substitution POE

If a=b, then a may be substituted for b in any equation or expression

congruent angles

two angles are (blank) if they have the same measure

congruent supplements theorem

If two angles are suppl. to the same angle or to congruent angles, then they are congruent

supplementary angles

two angles are (blank) if the sum of their measures is 180�

linear pair postulate

if two angles form a linear pair, then they are suppl.; that is, the sum of their measure is 180�

congruent complements theorem

if two angles are comple. to the same angle or to congruent angles, then they are congruent

vertical angle theorem

if two angles are vertical angles, then they are congruent

vertical angles

two angles are (blank) if their sides form two pairs of opposite rays

complementary angles

two angles are (blank) if the sum of their measures is 90�

linear pair

two adjacent angles are a (blank) if their non common sides are opposite rays

parallel lines

two lines are (blank) if they do not intersect

intersecting lines

are coplaner and have exactly on point in common

oblique lines

lines are (blank) if they intersect and do not form right angles

skew lines

lines are (blank) if they do not lie in the same plane

transitive property of parallel lines

if two lines are parallel to the same line, then they are parallel to each other

property of perpendicular lines

if 2 coplanar lines are perpendicular to the same line, then they are parallel to each other

perpendicular postulate

if there is a line and a point not on a line, them there is exactly one line through the point perpendicular to the given line

parallel postulate

if there is a line and a point not on the line, then there is exactly one line through the point parallel to the given line

If 2 distinct lines intersect...

...then their intersection is exactly one point.

If 2 lines are perpendicular,

then they are intersecting to form 4 right angles

All right angles are

congruent

If 2 lines intersect to form a pair of adjacent congruent angles,

then the 2 lines are perpendicular

tranversal

a line that intersects two or more coplanar lines at different points

corresponding angles

2 angles are (blank) if they occupy the same positions

alternate interior angles

2 angle are (blank) if they lie between line l and m on opposite sides of t

alternate exterior angles

2 angles are (blank) if they lie outside l and m on opposite sides of t

consecutive interior angles

2 angles are (blank) if they lie between l and m on the same side of t

corresponding angles postulate

if 2 lines are cut by a transversal so the corresponding angles are congruent, then the lines are parallel

alternate interior angles theorem

if 2 parallel lines are cut by a transversal, then the pairs of alternate interior angles are congruent

consecutive interior angles theorem

if 2 parallel lines are cut by a transversal, then the pairs of consecutive interior angles are supplementary

alternate exterior angles theorem

if 2 parallel lines are cut by a transversal, then the pairs of alternate exterior angles are congruent

perpendicular transversal theorem

if a transversal is perpendicular to one of two parallel lines, then is is perpendicular to the second

congruent triangles

If ?ABC is congruent to ?PQR, then there correspondence between their anglees and sidees such that corresponding angles are congruent and correspoonding sides are congruent

equilateral triangle

a triangle with 3 congruent sides

isosceles triangle

a triangle with at least 2 congruent sides

scalene triangle

a triangle with no congruent sides

acute triangle

a triangle with 3 acute angles

equiangular triangle

a triangle with 3 congruent; each with a measure of 60�

right triangle

a triangle with exactly one right angle

obtuse triangle

a triangle with exactly one obtuse angle

interior of a triangle

the original 3 angles of the triangle

exterior of a triangle

the angles adjacent to the interior angle

Triangle Sum Theorem

The sum of the measure of the interior angles of the trianlge is 180�

Third Angles Theorem

if 2 angles of one triangle are congruent to the 2 angles of a second triangle, then the 3rd angles are congruent

The acute angles of a rigt triangle are

complementary

exterior angle theorem

the measure of an exterior angle of a triangle is equal to the sum of the measures of the 2 nonadjacent interior angles

exterior angle inequality theorem

the measure of an exterior angle of a triangle is greater than the measure of either of the 2 nonadjacent inteior angles

angle addition postulate

If B is in the interior of ?AOC, then m?AOB + m?BOC = m?AOC

adjacent angles

Two angles are (blank) if they share a common vertex and side, but have no common interior points

angle

a (blank) consists of two different rays that have the same initial point. The rays are the sides of the (blank) and the initial point is the vertex of the (blank)

subtraction POE

If a=b, then a-c = b-c

obtuse angle

an angle with a measure greater than 90� and less than 180�

congruent segments

two segments are (blank) if they have the same length

segment bisector

a segment, ray, line, or plane that intersects a segment at its midpoint

division POE

If a=b and c?0, then a�0 = b�0

interior of an angle

every nonstriaght angle has an (blank). point D is in the (blank) of ?A if it is between points that lie on each side of the angle

Through any two distinct points...

...there exists exactly one line.

opposite rays

on the line AB, if C is between A and B, then CA-> and CB-> are (blank)

transitive POC

if one geometric object is congruent to a second, and the second is congruent to a third, then the first object is congruent to the third object.

straight angle

an angle with a measure of 180�

acute angle

an angle with a measure greater than 0� and less than 90�

symmetric POC

If one geometric object is congruent to a second, then the second object is congruent to the first.

Through any three non collinear points...

...there exists only one plane.

If two distinct points lie in a plane...

...then the line containing them lies in the plane.

exterior of an angle

Every non straight angle has a (blank). Point D is in the (blank) of ?A if it is not on sides of the angle or in the interior of the angle

multiplication POE

If a=b, then ac=bc

A line is perpendicular to a plane...

...if it is perpendicular to each line in the plane that intersects it.

right angle

an angle with a measure of 90�

reflexive POE

for any real number a, a=a

angle bisector

a ray that divides the angle into two congruent angles

line segment

AB, or (line above) AB, consists of the endpoints A and B and all points on (line with arrows above)AB that lie between A and B

transitive POE

If a=b and b=c, then a=c

midpoint of a segment

the point that divides the segment into two congruent segments

symmetric POE

If a=b, then b=a

addition POE

If a=b, then a+c = b+c

perpendicular lines

two lines are (blank) if they intersect to form a right angle

a line contains...

... at least two points.

reflexive POC

any geometric object is congruent to itself

a plane contains at least...

...three noncollinear points

if two distinct planes intersect...

...then their intersection is a line

collinear

points, segments, or rays that are on the same line

ray

ray AB, or (line with one arrow head to the right) AB, consists of the initial point A and all points on (line with two arrow heads) AB that lie on the same side of A as B lies

segment addition postulate

If B is between A and C, then AB + BC = AC

substitution POE

If a=b, then a may be substituted for b in any equation or expression

congruent angles

two angles are (blank) if they have the same measure

congruent supplements theorem

If two angles are suppl. to the same angle or to congruent angles, then they are congruent

supplementary angles

two angles are (blank) if the sum of their measures is 180�

linear pair postulate

if two angles form a linear pair, then they are suppl.; that is, the sum of their measure is 180�

congruent complements theorem

if two angles are comple. to the same angle or to congruent angles, then they are congruent

vertical angle theorem

if two angles are vertical angles, then they are congruent

vertical angles

two angles are (blank) if their sides form two pairs of opposite rays

complementary angles

two angles are (blank) if the sum of their measures is 90�

linear pair

two adjacent angles are a (blank) if their non common sides are opposite rays

parallel lines

two lines are (blank) if they do not intersect

intersecting lines

are coplaner and have exactly on point in common

oblique lines

lines are (blank) if they intersect and do not form right angles

skew lines

lines are (blank) if they do not lie in the same plane

transitive property of parallel lines

if two lines are parallel to the same line, then they are parallel to each other

property of perpendicular lines

if 2 coplanar lines are perpendicular to the same line, then they are parallel to each other

perpendicular postulate

if there is a line and a point not on a line, them there is exactly one line through the point perpendicular to the given line

parallel postulate

if there is a line and a point not on the line, then there is exactly one line through the point parallel to the given line

If 2 distinct lines intersect...

...then their intersection is exactly one point.

If 2 lines are perpendicular,

then they are intersecting to form 4 right angles

All right angles are

congruent

If 2 lines intersect to form a pair of adjacent congruent angles,

then the 2 lines are perpendicular

tranversal

a line that intersects two or more coplanar lines at different points

corresponding angles

2 angles are (blank) if they occupy the same positions

alternate interior angles

2 angle are (blank) if they lie between line l and m on opposite sides of t

alternate exterior angles

2 angles are (blank) if they lie outside l and m on opposite sides of t

consecutive interior angles

2 angles are (blank) if they lie between l and m on the same side of t

corresponding angles postulate

if 2 lines are cut by a transversal so the corresponding angles are congruent, then the lines are parallel

alternate interior angles theorem

if 2 parallel lines are cut by a transversal, then the pairs of alternate interior angles are congruent

consecutive interior angles theorem

if 2 parallel lines are cut by a transversal, then the pairs of consecutive interior angles are supplementary

alternate exterior angles theorem

if 2 parallel lines are cut by a transversal, then the pairs of alternate exterior angles are congruent

perpendicular transversal theorem

if a transversal is perpendicular to one of two parallel lines, then is is perpendicular to the second

congruent triangles

If ?ABC is congruent to ?PQR, then there correspondence between their anglees and sidees such that corresponding angles are congruent and correspoonding sides are congruent

equilateral triangle

a triangle with 3 congruent sides

isosceles triangle

a triangle with at least 2 congruent sides

scalene triangle

a triangle with no congruent sides

acute triangle

a triangle with 3 acute angles

equiangular triangle

a triangle with 3 congruent; each with a measure of 60�

right triangle

a triangle with exactly one right angle

obtuse triangle

a triangle with exactly one obtuse angle

interior of a triangle

the original 3 angles of the triangle

exterior of a triangle

the angles adjacent to the interior angle

Triangle Sum Theorem

The sum of the measure of the interior angles of the trianlge is 180�

Third Angles Theorem

if 2 angles of one triangle are congruent to the 2 angles of a second triangle, then the 3rd angles are congruent

The acute angles of a rigt triangle are

complementary

exterior angle theorem

the measure of an exterior angle of a triangle is equal to the sum of the measures of the 2 nonadjacent interior angles

exterior angle inequality theorem

the measure of an exterior angle of a triangle is greater than the measure of either of the 2 nonadjacent inteior angles