D

Data A set of numerical facts

Data base A collection of data that is organized and stored electronically for rapid search, retrieval and editing.

Decagon A polygon having ten sides.

Decimal notation Our notation for writing numerals using the Hindu-Arabic numerals and place values based on the powers of ten

Decimal numeral A numeral which contains a decimal point and is used for a fraction

Decimal point The dot in a decimal numeral which shows where the one's place is in the numeral

Degree of a polynomial   The exponent of the highest power term in a polynomial.

Degree The most common unit of measurement for angles.

Denominator The bottom portion of a fraction

Density   The mass per unit volume of a substance.

Dependent events   Two events in which the result of the first affects the result of the second.

Diagonal  0 A segment that joins two consecutive vertices of a polygon.

Diagonal (of polygon) A line segment that joins two non-consecutive vertexes of a polygon

Diameter  , 0 A chord that contains the center of a circle or a sphere.  Also, the length of such a chord.

Diameter A line segment which contains the center of a circle and Whose endpoints are two points of the circle

Digit Each basic (single) numeral which names a number

Direct measurement A measurement made by comparing an object directly with a standard unit of measure

Discount The amount deducted from the original amount.

Distributive property of multiplication over addition For each number a, each number b, and each number

c, a x (b + c) (a x b) + (a x c)

Distributive property The sum of two addends multiplied by a number is the sum of the product of each addend

and the number. For any numbers a. b and c, a x (b+c) = a x b+ a x c.

Dividend A number divided by another number (divisor) resulting in a qoutient.

Divisible A number is divisible by another if the quotient is a whole number and the remainder is zero.

Division property of  equality If each side of an equaltion is divided by the same nonzero number, then the two

sides remain equal. If a = b, then a/c = b/c, c¹ 0.

Division Separating into parts or portions.

Divisor (in division) The number by which the dividend is to be divided

Divisor (of number) A non-zero factor of a number

Divisor One of two or more integers that can be exactly divided into another integer . e number that is divided

into another number (dividend) resulting in a quotient.

Dodecagon A polygon having twelve sides.