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Mixed Number

the sum of a whole number and a fraction

Line

straight line that has no width and no ends

Line Segment

part of a line

Intersect

when two lines cross

Point of Intersection

the place where two lines cross

Parallel Lines

lines in the same plane that do not intersect and the distance between the lines is always the same

Perpendicular

when two lines make square corners at the point of intersection

Right Angles

the angles made by perpendicular lines

Straight Angle

two right angles that forms a straight line back to back

Acute Angle

an angle smaller than a right angle

Obtuse Angle

an angle larger than a right angle

Polygon

simple, closed, flat geometric figures whose sides are line segments and whose lines do not cross

Triangle

a polygon with 3 sides and vertices

Quadrilateral

a polygon with 4 sides and vertices

Pentagon

a polygon with 5 sides and vertices

Hexagon

a polygon with 6 sides and vertices

Heptagon

a polygon with 7 sides and vertices

Octagon

a polygon with 8 sides and vertices

Nonagon

a polygon with 9 sides and vertices

Decagon

a polygon with 10 sides and vertices

Undecagon

a polygon with 11 sides and vertices

Dodecagon

a polygon with 12 sides and vertices

Concave

an indentation

Concave Polygon

a polygon with an indentation

Convex Polygon

any polygon without an indentation

Equilateral Polygon

when all the sides of a polygon have the same length

Equiangular Polygon

when all the angles of a polygon have the same measure

Regular Polygons

when all the sides of a polygon are the same length and all the angles are the same measure

Tick Marks

marks used to denote sides and angles that have the same length and/or measure

Right Triangle

a triangle with a right angle

Acute Triangle

a triangle with angles smaller than 90 degrees

Obtuse Triangle

a triangle with an angle that is greater than 90 degrees

Equianglular Triangle

a triangle in which all the angles are the same measure

Isoceles Triangle

a triangle that has at least two sides of equal length

Equilateral Triangle

a triangle in which the length of all the sides are equal

Scalene Triangle

a triangle in which all sides are different

Parallelogram

a quadrilateral that has two pairs of parallel sides

Trapezoid

a quadrilateral that has exactly two parallel sides

Rectangle

a parallelogram with four right angles

Rhombus

an equilateral parallelogram

Square

a rhombus with four right angles

Perimeter

the measure around

Radius

the distance from the center of the circle to the outside edge

Diameter

the distance from one side of a circle through the center to the other side

Circumference

the perimeter of a circle

Irrational Number

a number that would take an infinite number of digits to express

Number

an idea that represents quantity

Numeral

a symbol which represents the idea of a particular number

Value

the number represented by a numeral

Natural Numbers

counting numbers

Positive Real Numbers

any number that can be used to describe a physical distance greater than zero

Zero

a number that can be used to describe a physical distance of no magnitude

Real Numbers

all the positive real numbers plus zero

Negative Numbers

the negative counterparts of the positive real numbers

Signed Numbers

numbers that are indicated with signs of postive or negative used in algebraic addition

Symbol of Equality

the equal sign which indicates that two quantities are equal

Symbol of Inequality

the unequal sign which indicates that two quantities are not equal

Addend

the numbers added in an addition problem

Sum

the result of an addition problem

Minuend

the first number in a subtraction problem

Subtrahend

the second number in a subtraction problem

Difference

the result of a subtraction problem

Factor

the numbers multiplied in a multiplication problem

Product

the result of a multiplication problem

Dividend

the first number in a division problem

Divisor

the second number in a division problem

Quotient

the result of a division problem

Numerator

the number on the top of a fraction

Denominator

the number on the bottom of a fraction