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Chord

A segment inside the circle which has end points on the sides of the circle.

Hexagon

a polygon with six sides

180

Total measure the angles in every triangle.

Rhombus

A quadrilateral, parallelogram with 4 congruent sides

Scalene

A triangle with NO sides congruent

Square

A quadrilateral, parallelogram with 4 congruent sides and 4 right angles

Supplementary

Angles whose sum is 180

Straight

An angle that measures exactly 180

Obtuse

An angle that measures between 90-180

Nonagon

A polygon with 9 sides

Line

A series of points that extends indefinitely in both directions

Right

An angle that measures exactly 90

Right Triangle

A triangle with1 right angle

Regular Polygon

A polygon with ALL sides congruent and ALL angles congruent

Ray

Part of a line that extends indefinitely in ONE direction with ONE end point

Parallel lines

Lines that NEVER intersect

Rectangle

A quadrilateral, parallelogram with 4 right angles

Equilateral

A triangle with 3 congruent sides

Triangle

A polygon with 3 sides

Skew lines

Lines that are NOT in the same plane, that are NOT parallel, and do NOT intersect

Radius

A segment that connects the center of the circle to any point on the edge of the circle

Trapezoid

A quadrilateral with exactly ONE pair of parallel sides.

Diameter

A chord that crosses through the center of the circle

Complementary

Angles whose sum is 90

Decagon

A polygon with 10 sides

Congruent Sides

Sides that are equal

Congruent Angles

Angles with equal measures

Acute

An angle that measures between 0-90

Parallelogram

A quadrilateral with 2 pairs of parallel lines

Octagon

A polygon with 8 sides

Semicircle

An arc that is exactly half of the circumference; use the diameter as a side

Acute Triangle

has 3 Acute angles

Segment

Part of a line with 2 endpoints

Vertical

Angles that are across from each other; they share a vertex only

Circle

A series of points equidistant from a given point, the center; NOT A POLYGON

Heptagon

A polygon with 7 sides

Obtuse Triangle

A triangle with 1 obtuse angle

Pentagon

A polygon with 5 sides

Vertex

The intersection of two segments or rays

Plane

A flat surface that extends indefinitely in all directions

Point

Indicates a location

Quadrilateral

Any Polygon with 4 sides

Adjacent

Angles that are next to each other; share a side and vertex

Intersecting lines

lines or segments that have one point in common; they cross over each other

Angle

Formed by the intersection of two rays or segments

Irreagular Polygon

When all sides and angles are NOT congruent

Arc

Outside portion of a circle between two points

Isosceles

A triangle with 2 congruent sides

Central Angle

An angle inside the circle that has the center of the circle as a vertex of the angle