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parallel lines

skew lines

parallel planes

transversal

Coplanar lines that do not intersect.

Lines that do not intersect and are not coplanar.

Two planes that do not intersect.

A line that intersects two coplanar lines at two distinct poi…

parallel lines

Coplanar lines that do not intersect.

skew lines

Lines that do not intersect and are not coplanar.

parallel lines

parallel planes

distance from a point to a line

skew lines

Coplanar lines that do not intersect

Planes that do not intersect

The length of the perpendicular segment from the point to the…

Lines that do not intersect and are not coplanar

parallel lines

Coplanar lines that do not intersect

parallel planes

Planes that do not intersect

Obtuse Angle

Acute Angle

Right Angle

Reflex Angle

An angle between 90 and 180 degrees

Angles measuring less than 90 degrees.

Angles measuring 90 degrees.

An angle with a measurement between 180 and 360 degrees.

Obtuse Angle

An angle between 90 and 180 degrees

Acute Angle

Angles measuring less than 90 degrees.

Alternate Exterior Angles

Alternate Interior Angles

Consecutive Interior Angles

Corresponding Angles

Two angles that are formed by two lines and a transversal tha…

Two angles that are formed by two lines and a transversal tha…

Two angles that are formed by two lines and a transversal tha…

Two angles that are formed by two lines and a transversal tha…

Alternate Exterior Angles

Two angles that are formed by two lines and a transversal tha…

Alternate Interior Angles

Two angles that are formed by two lines and a transversal tha…

Alternate Exterior Angles

Alternate Interior Angles

Consecutive Interior Angles

Corresponding Angles

Two angles that are formed by two lines and a transversal tha…

Two angles that are formed by two lines and a transversal tha…

Two angles that are formed by two lines and a transversal tha…

Two angles that are formed by two lines and a transversal tha…

Alternate Exterior Angles

Two angles that are formed by two lines and a transversal tha…

Alternate Interior Angles

Two angles that are formed by two lines and a transversal tha…

skew lines

transversal

corresponding

consecutive

never intersect, not on the same plane (ex. floor and wall)

line that intersects +2 coplanar (same plane) lines at differ…

same spot in a different place congruent

same side interior supplementary

skew lines

never intersect, not on the same plane (ex. floor and wall)

transversal

line that intersects +2 coplanar (same plane) lines at differ…

angle-angle similarity

angle

congruent

corresponding sides

if two angles of one triangle are congruent to two correspond…

in geometric figures, usually formed by two segments with a c…

exactly the same shape and size

sides in two or more figures that are images of each other wi…

angle-angle similarity

if two angles of one triangle are congruent to two correspond…

angle

in geometric figures, usually formed by two segments with a c…

parallel lines

skew lines

parallel planes

transversal

Coplanar lines that do not intersect.

Lines that do not intersect and are not coplanar.

Two planes that do not intersect.

A line that intersects two coplanar lines at two distinct poi…

parallel lines

Coplanar lines that do not intersect.

skew lines

Lines that do not intersect and are not coplanar.

Parallel Postulate

Perpendicular Postulate

Corresponding Angles Theorem

Alternate Interior Angles Theorem

If there is a line and a point not on the line, then there is…

If there is a line and a point not on the line, then there is…

If two parallel lines are cut by a transversal, then the pair…

If two parallel lines are cut by a transversal, then the pair…

Parallel Postulate

If there is a line and a point not on the line, then there is…

Perpendicular Postulate

If there is a line and a point not on the line, then there is…

Alternate Interior Angles

Alternate Exterior Angles Converse

Parallel Lines

Parallel Planes

Between 2 lines, on opposite sides of the transversal

If Alternate Exterior Angles are congruent, then the lines ar…

Coplanar lines that never intersect

Planes that never intersect

Alternate Interior Angles

Between 2 lines, on opposite sides of the transversal

Alternate Exterior Angles Converse

If Alternate Exterior Angles are congruent, then the lines ar…

Alternate Exterior Angles

Alternate Interior Angles

Consecutive Interior Angles

Corresponding Angles

Two angles that are formed by two lines and a transversal tha…

Two angles that are formed by two lines and a transversal tha…

Two angles that are formed by two lines and a transversal tha…

Two angles that are formed by two lines and a transversal tha…

Alternate Exterior Angles

Two angles that are formed by two lines and a transversal tha…

Alternate Interior Angles

Two angles that are formed by two lines and a transversal tha…

skew lines

parallel lines

parallel planes

transversal

lines that do not intersect and are no coplanar

lines that do not intersect and are coplanar

two planes that do no intersect

a line that intersects two or more coplanar lines at differen…

skew lines

lines that do not intersect and are no coplanar

parallel lines

lines that do not intersect and are coplanar

Parallel Lines

Skew Lines

Parallel planes

Transversal

Coplanar lines that do not intersect

Lines that do not intersect and are not coplanar

Planes that do not intersect

A line that intersects two or more lines.

Parallel Lines

Coplanar lines that do not intersect

Skew Lines

Lines that do not intersect and are not coplanar

Segment bisector

Perpendicular bisector

Perpendicular Bisector Conjecture

Converse of the Perpendicular Bisector…

A line, ray, or segment that passes through the midpoint of a…

A line or segment that divides a line segment into two equal…

If a point is on the perpendicular bisector of a segment, the…

If a point is equidistant from the endpoints of a segment, th…

Segment bisector

A line, ray, or segment that passes through the midpoint of a…

Perpendicular bisector

A line or segment that divides a line segment into two equal…

Alternate Interior Angles

Alternate Exterior Angles

Corresponding Angles

Same Side Interior Angles

Nonadjacent interior that lie on opposite sides of a transver…

Nonadjacent exterior angles that lie on opposite sides of the…

Angles that lie on the same side of the traversal and in corr…

Interior angles that lie on the same side of the transversal.…

Alternate Interior Angles

Nonadjacent interior that lie on opposite sides of a transver…

Alternate Exterior Angles

Nonadjacent exterior angles that lie on opposite sides of the…

Vertical Angles

Linear Pair

Supplementary Angles

Angle

Two nonadjacent angles who share a common initial point and t…

Two adjacent angles that together form a line.

Two angles whose sum is 180 degrees.

Formed when two rays share an initial point.

Vertical Angles

Two nonadjacent angles who share a common initial point and t…

Linear Pair

Two adjacent angles that together form a line.

Parallel Lines

Skew lines

Transversal

Parallel Postulate

When two or more lines lie in the same plane and never inters…

Lines that are in different planes and never intersect.

A line that intersects two or more lines in different points

If there is a line and a point not on a line, then there is e…

Parallel Lines

When two or more lines lie in the same plane and never inters…

Skew lines

Lines that are in different planes and never intersect.

Segment bisector

Perpendicular bisector

Perpendicular Bisector Conjecture

Converse of the Perpendicular Bisector…

A line, ray, or segment that passes through the midpoint of a…

A line or segment that divides a line segment into two equal…

If a point is on the perpendicular bisector of a segment, the…

If a point is equidistant from the endpoints of a segment, th…

Segment bisector

A line, ray, or segment that passes through the midpoint of a…

Perpendicular bisector

A line or segment that divides a line segment into two equal…

Parallel lines

Skew lines

Parallel planes

Transversal

coplanar lines that do not intersect

Lines that do not intersect and are not coplanar

two planes that do not intersect

a line that intersects two or more coplanar lines at differen…

Parallel lines

coplanar lines that do not intersect

Skew lines

Lines that do not intersect and are not coplanar

Parallel Lines

Skew Lines

Parallel Planes

If two parallel planes are cut by a th…

COPLANAR lines that do not intersect

NON coplanar lines that to not intersect (think left/right an…

Planes that do not intersect (Think floor and ceiling)

If planes X and Y are parallel, then their lines of intersect…

Parallel Lines

COPLANAR lines that do not intersect

Skew Lines

NON coplanar lines that to not intersect (think left/right an…

parallel lines

skew lines

parallel planes

transversal

coplanar lines that do not intersect

lines that do not intersect and are not coplanar

planes that do not intersect

a line that intersects two or more lines in a plane at differ…

parallel lines

coplanar lines that do not intersect

skew lines

lines that do not intersect and are not coplanar

Alternate Interior Angles (AIA)

Alternate Exterior Angles (AEA)

Corresponding Angles (CA)

Exterior Angle of Triangle

Nonadjacent inside angles that lie on opposite sides of the t…

Nonadjacent outside angles that lie on opposite sides of the…

One inside angle and one outside angle that lie on the same s…

Each exterior of a triangle equals the sum of the measures of…

Alternate Interior Angles (AIA)

Nonadjacent inside angles that lie on opposite sides of the t…

Alternate Exterior Angles (AEA)

Nonadjacent outside angles that lie on opposite sides of the…

similarity

dilation

point of dilation / stretch point

scale factor / zoom factor

-same shape, but not necessarily the same size... -angles are co…

-a transformation where a point on a figure is stretched prop…

-the point of a figure that is stretched to form a dilation o…

-the number a side is multiplied by to make a bigger or small…

similarity

-same shape, but not necessarily the same size... -angles are co…

dilation

-a transformation where a point on a figure is stretched prop…

Parallel Lines

Perpendicular lines

Skew lines

Parallel Planes

Coplanar lines that do not intersect.... Their equations have th…

Lines that intersect at 90 degree angles.... Their slopes have a…

Lines that are not coplanar, not parallel and do not intersect.

Planes that do not intersect

Parallel Lines

Coplanar lines that do not intersect.... Their equations have th…

Perpendicular lines

Lines that intersect at 90 degree angles.... Their slopes have a…

Corresponding Angles

Alternate Interior Angles

Alternate Exterior Angles

Same Side Interior Angles

Angles in the same position

Changing position and inside the line

Changing position and outside the line

Changing top to bottom not left to right and inside the lines

Corresponding Angles

Angles in the same position

Alternate Interior Angles

Changing position and inside the line

angle-angle similarity

angle

congruent

corresponding sides

if two angles of one triangle are congruent to two correspond…

in geometric figures, usually formed by two segments with a c…

exactly the same shape and size

sides in two or more figures that are images of each other wi…

angle-angle similarity

if two angles of one triangle are congruent to two correspond…

angle

in geometric figures, usually formed by two segments with a c…

skew lines

parallel lines

parallel planes

transversal

lines that do not intersect and are no coplanar

lines that do not intersect and are coplanar

two planes that do no intersect

a line that intersects two or more coplanar lines at differen…

skew lines

lines that do not intersect and are no coplanar

parallel lines

lines that do not intersect and are coplanar

Alternate Interior Angles

Alternate Exterior Angles

Corresponding Angles

Same Side Interior Angles

Nonadjacent interior that lie on opposite sides of a transver…

Nonadjacent exterior angles that lie on opposite sides of the…

Angles that lie on the same side of the traversal and in corr…

Interior angles that lie on the same side of the transversal.…

Alternate Interior Angles

Nonadjacent interior that lie on opposite sides of a transver…

Alternate Exterior Angles

Nonadjacent exterior angles that lie on opposite sides of the…

Parallel Lines

Skew Lines

Parallel Planes

Transversal

2 lines that do not intersect and are coplaner

2 lines that do not intersect and are not coplaner

2 planes that do not intersect

A line that intersects 2 or more coplaner lines at different…

Parallel Lines

2 lines that do not intersect and are coplaner

Skew Lines

2 lines that do not intersect and are not coplaner

segment bisector

perpendicular bisector

median

coincide

A line, ray, or segment that passes through the midpoint of a…

A line that divides a line segment into two congruent parts a…

A line segment connecting a vertex of a triangle to the midpo…

To lie exactly on top of each other.

segment bisector

A line, ray, or segment that passes through the midpoint of a…

perpendicular bisector

A line that divides a line segment into two congruent parts a…

Postulate 3-1 Same-side Interior Angle…

Theorem 3-1 Alternate Interior Angles…

Theorem 3-2 Corresponding Angles Theor…

Theorem 3-3 Alternate Exterior Angles…

supplementary... m∠1 + m∠2 = 180

congruent

corresponding

exterior

Postulate 3-1 Same-side Interior Angle…

supplementary... m∠1 + m∠2 = 180

Theorem 3-1 Alternate Interior Angles…

congruent

vertical angles

linear pair

corresponding angles

same side interior angles

angles which share a vertex, but not sides; they are always c…

adjacent angles that are supplementary

an angle pair with one interior and one exterior angle on the…

angles on the same side of the transversal that are between t…

vertical angles

angles which share a vertex, but not sides; they are always c…

linear pair

adjacent angles that are supplementary

AA~

dilation

flowchart

logical argument

If two angles of one triangle are congruent to the two corres…

A transformation which produces a figure similar to the origi…

A diagram showing an argument for a conclusion from certain e…

A logical sequence of statements and reasons that lead to a c…

AA~

If two angles of one triangle are congruent to the two corres…

dilation

A transformation which produces a figure similar to the origi…

Vertical Angles

Adjacent Angles

Complementary Angles

Supplementary Angles

Share a vertex, don't an overlap and don't share a side. They…

Angles that are next to each other, share a vertex, and share…

Two angles that add up to 90 degrees

Two angles that add up to 180 degrees

Vertical Angles

Share a vertex, don't an overlap and don't share a side. They…

Adjacent Angles

Angles that are next to each other, share a vertex, and share…

corresponding Angles Postulate

Alternate Interior Angles Theorem

Alternate Exterior angles theorem

Same -Side Interior Angles Theorem

If two parallel lines are cut by a transversal, then the pair…

If two parallel lines are cut by a transversal, then the pair…

If two parallel lines are cut by a transversal, then the two…

If two parallel lines are cut by a transversal, then the two…

corresponding Angles Postulate

If two parallel lines are cut by a transversal, then the pair…

Alternate Interior Angles Theorem

If two parallel lines are cut by a transversal, then the pair…

parallel lines

skew lines

corresponding angles

alternate interior angles

Coplanar lines that do not intersect

Non-coplanar lines that do not intersect

congruent angles in corresponding positions of parallel lines…

congruent angles that lie between parallel lines and are loca…

parallel lines

Coplanar lines that do not intersect

skew lines

Non-coplanar lines that do not intersect

parallel lines

skew lines

parallel planes

perpendicular lines

lines that are coplanar and do NOT intersect

lines that are NOT coplanar and do not intersect

two planes that do NOT intersect

lines that intersect at a 90º angle

parallel lines

lines that are coplanar and do NOT intersect

skew lines

lines that are NOT coplanar and do not intersect

Parallel Lines

Skew Lines

Transversal

Interior Angles

Coplanar lines that don't intersect ... II symbol

Non coplanar lines that don't intersect

Line that intersects 2 or more coplanar lines at distinct poi…

Formed by transversal that lie between 2 intersected lines

Parallel Lines

Coplanar lines that don't intersect ... II symbol

Skew Lines

Non coplanar lines that don't intersect

Parallel Lines

Skew Lines

Parallel Planes

Transversal

Lines that are coplanar and do not intersect

Lines that do not intersect and are not coplanar

Two planes that do not intersect

a line that intersects two or more lines at different points

Parallel Lines

Lines that are coplanar and do not intersect

Skew Lines

Lines that do not intersect and are not coplanar

parallel lines

perpendicular lines

skew lines

perpendicular bisector

lines which are coplanar and do not intersect

lines which intersect at 90˚ angles

lines which are not coplanar

a line perpendicular to a segment at the segment's midpoint

parallel lines

lines which are coplanar and do not intersect

perpendicular lines

lines which intersect at 90˚ angles

Alternate Interior Angles

Alternate Exterior Angles

Corresponding Angles

Same Side Interior Angles

Nonadjacent interior that lie on opposite sides of a transver…

Nonadjacent exterior angles that lie on opposite sides of the…

Angles that lie on the same side of the traversal and in corr…

Interior angles that lie on the same side of the transversal.…

Alternate Interior Angles

Nonadjacent interior that lie on opposite sides of a transver…

Alternate Exterior Angles

Nonadjacent exterior angles that lie on opposite sides of the…

Polygon

Equilateral Polygon

Equiangular Polygon

Regular Polygon

A closed plane figure where the edges are not curved and each…

A polygon with all congruent sides.

A polygon with all congruent angles.

A polygon that is both equilateral and equiangular.

Polygon

A closed plane figure where the edges are not curved and each…

Equilateral Polygon

A polygon with all congruent sides.