an exact spot in space

Point

straight path that continues infinitely in two directions

Line

part of a line with two endpoints

Line segment

part of a line with one endpoint and one arrow that goes on forever

Ray

an endless flat surface

Plane

lines that never intersect

parallel

lines that cross at a 90 degree angle

perpendicular

lines that pass through the same point

intersecting lines

90 degrees

a right angle

less than 90 degrees

acute angle

greater than 90 degrees but less than 180 degrees

obtuse angle

180 degrees

a straight angle

same exact measurement(s)

congruent

Two angles whose sum is 180°

supplementary angles

Two angles whose sum is 90°.

Complementary angles

the pairs of opposite angles made by two intersecting lines (they will be congruent)

vertical angles

angles that are right next to each other

adjacent angles

two angles in the same relative position at each intersection in a transversal (where a straight lines cross two parallel lines). These angles are congruent.

corresponding angles

parallel lines are intersected by another line, the intersecting line is called a ______________________

transversal

Each pair of these angles are inside the parallel lines, and on opposite sides of the transversal (these angles are congruent)

alternate interior angles

a pair of angles on the outer side of each of those two parallel lines but on opposite sides of the transversal (these angles are congruent)

Alternate Exterior Angles

the two inside angles on the same side in a traversal will equal _____

180 degrees (same-side interior angles)

where two or more line segments or rays meet.

vertex

a ruler with no markings on it

straight edge

tool used to draw circles and arcs (parts of circles)

compass

size of a 2D surface

area

distance around a 2D shape

perimeter

line segment with end points on a circle

chord

distance around a circle

circumference

Figures with corresponding angles that are equal and corresponding sides that are proportional

similar

A chord that passes through the center of the circle from one edge to another

diameter

A line segment from the center of a circle to the edge

radius

The total area on all sides (surfaces) of a figure

surface area

The movement of objects in the coordinate plane where image is either similar to or congruent to the pre-image.

transformation

A Slide, Each vertex moves the same distance in the same directions

translation

A turn, Each vertex is rotated the number of degrees around a rotation point

rotation

A Flip, Each vertex is flipped across a line of reflection to result in a mirror image.

reflection

a line, segment or ray that goes through the midpoint of a segment

bisector

A point on a line segment that divides it into two equal parts.

midpoint

a part of the circumference of a circle or other curve

arc

The amount of space an object takes up.

volume

a quadrilateral with four right angles and 4 congruent sides

square

a quadrilateral with four right angles

rectangle

a quadrilateral with four congruent sides

rhombus

A quadrilateral with two sets of congruent lines that are adjacent to each other.

kite

A triangle with all acute angles

acute triange

A triangle with one obtuse angle and two acute angles

obtuse triangle

A triangle with one 90 degree angle

right triangle

A triangle with all congruent sides

equilateral triangle

A triangle with at least two congruent sides

isosceles

A triangle with no congruent sides

scalene triangle

quadrilateral with both pairs of opposite sides are parallel

parallelogram

A closed figure formed by three or more line segments that do not cross.

polygon

four sided polygon

four sided polygon

A polygon with congruent sides and angles

regular polygon

a quadrilateral with exactly one pair of parallel sides

trapezoid

A set of points in the same plane equal distance from the center.

circle

A set of all points in space that are the same distance from the center point.

sphere

A 3D object where the rectangular faces are perpendicular to the base shape. The base can be any shape.

right prism

3D object with a circular base and one vertex

cone

A prism with triangular faces that meet at one point, a vertex and base that is a polygon.

pyramid

A prism with two congruent parallel bases that are circles.

cylinder

A rectangular prism with faces that are all squares

cube

A line that intersects a curve (or circle) in at least two distinct points.

Secant

A line that touches a curve (or circle) at exactly one point.

Tangent (to a circle)

An angle whose vertex is the center O of a circle and whose legs (sides) are radii intersecting the circle in two distinct points A and B.

Central Angle

*Secondary 2 and higher only*

The ratio between the side opposite of an angle and the hypotenuse.

*Secondary 2 and higher only*

Sine

*Secondary 2 and higher only*

The ratio between the side adjacent to an angle and the hypotenuse.

*Secondary 2 and higher only*

Cosine

*Secondary 2 and higher only*

The ratio between the side opposite of an angle and the side adjacent to the angle.

*Secondary 2 and higher only*

Tangent (as a triangle ratio)

*Secondary 2 and higher only*

Exterior Angles Theorem

*Secondary 2 and higher only*

The exterior angle of a triangle is equal to the sum of the two opposite interior angles