McGraw-Hill OnlineMcGraw-Hill Higher EducationLearning Center
Student Center | Instructor Center | Information Center | Home
GED Practice Test
Formulas
Alternate Grids
Calculator Directions
GED Score
Glossary
Math Handbook
GED Links
Feedback
Help Center


Contemporary's GED Mathematics
Jerry Howett


Glossary

Below is a list of key terms that appear in Contemporary's GED Mathematics. Click on the links within the definitions to view interactive flashcards for the key terms by chapter.
absolute value  the distance from a number to zero on the number line (CHAPTER 10 FLASHCARDS)
(See page 282 in your textbook.)
acute angle  an angle measuring less than 90° (CHAPTER 9 FLASHCARDS)
(See page 225 in your textbook.)
adjacent angles  angles that share one side (CHAPTER 9 FLASHCARDS)
(See page 229 in your textbook.)
adjacent sides  sides in a polygon that share a vertex (CHAPTER 9 FLASHCARDS)
(See page 232 in your textbook.)
algebra  an extension of the basic operations of arithmetic in which letters are used to represent numbers (CHAPTER 10 FLASHCARDS)
(See page 281 in your textbook.)
algebraic expression  a translation of a mathematical relationship using basic arithmetic operations (for example, the phrase a number increased by four can be written as x + 4 or 4 + x) (CHAPTER 10 FLASHCARDS)
(See page 306 in your textbook.)
angle  a figure formed by two rays extending from the same point (CHAPTER 9 FLASHCARDS)
(See page 224 in your textbook.)
area  a measure of the amount of surface on a closed plane figure (CHAPTER 9 FLASHCARDS)
(See page 240 in your textbook.)
associative property  for addition and multiplication, three numbers can be grouped in any order; the sum or product will be the same; for any numbers a, b, and c, (a + b) + c = a + (b + c) and (ab)c = a(bc) (CHAPTER 1 FLASHCARDS)
(See page 40 in your textbook.)
average  the sum of a set of numbers divided by the number of numbers in the set; another name for mean (CHAPTER 8 FLASHCARDS)
(See page 217 in your textbook.)
base  one of the factors in a power (for example, in 32 the base is 3 and the exponent is 2); in geometry, the side or face of a figure to which the height is drawn (CHAPTER 1 FLASHCARDS)
(See page 32 in your textbook.)
base angles  the two equal angles in an isosceles triangle (CHAPTER 9 FLASHCARDS)
(See page 259 in your textbook.)
borrowing  regrouping or renaming a fraction in a subtraction problem (for example, 9 – 2 1/4 = 8 4/4 – 2 1/4) (CHAPTER 4 FLASHCARDS)
(See page 118 in your textbook.)
canceling  a shortcut for multiplying fractions which involves finding a number that divides evenly into the numerator of one fraction and the denominator of another (CHAPTER 4 FLASHCARDS)
(See page 121 in your textbook.)
circle  a plane figure, each point of which is the same distance from the center (CHAPTER 9 FLASHCARDS)
(See page 232 in your textbook.)
circumference  the distance around a circle (CHAPTER 9 FLASHCARDS)
(See pages 232 and 234 in your textbook.)
common denominator  for a set of fractions, a number into which each denominator can divide evenly (CHAPTER 4 FLASHCARDS)
(See page 114 in your textbook.)
commutative property  for addition and multiplication, numbers can be added or multiplied in any order; the sum or product will be the same; for any numbers a and b, a + b = b + a and ab = ba (CHAPTER 1 FLASHCARDS)
(See page 39 in your textbook.)
compatible pairs  numbers that divide evenly (for example, 80 and 4,800) (CHAPTER 1 FLASHCARDS)
(See page 26 in your textbook.)
complementary angles  angles whose sum is 90° (CHAPTER 9 FLASHCARDS)
(See page 228 in your textbook.)
cone  a 3-dimensional figure whose base is a circle and whose height is the perpendicular distance from the base to the vertex (CHAPTER 9 FLASHCARDS)
(See page 250 in your textbook.)
congruent figures  geometric figures with exactly the same shape and the same size (CHAPTER 9 FLASHCARDS)
(See page 267 in your textbook.)
consecutive numbers  one number following the other (for example, 19 and 20) (CHAPTER 1 FLASHCARDS)
(See page 20 in your textbook.)
convert  to change from one unit of measure to another (CHAPTER 7 FLASHCARDS)
(See page 184 in your textbook.)
coordinate plane  a flat surface divided by a horizontal x-axis and a vertical y-axis (CHAPTER 11 FLASHCARDS)
(See page 323 in your textbook.)
coordinates  a pair of numbers in the form (x, y) that identify the distance of a point from the origin or center on the coordinate plane; the first number tells the distance to the left or right of the vertical axis, and the second number tells the distance above or below the horizontal axis (CHAPTER 11 FLASHCARDS)
(See page 323 in your textbook.)
corresponding sides  the matching sides of similar figures; pairs of corresponding sides can be written as a proportion (CHAPTER 9 FLASHCARDS)
(See page 263 in your textbook.)
cosine  for an acute angle in a right triangle, the ratio of the adjacent side to the hypotenuse; abbreviated as cos (CHAPTER 11 FLASHCARDS)
(See page 343 in your textbook.)
cross products  in a statement with two equal fractions, the numerator of the first fraction multiplied by the denominator of the second fraction and the numerator of the second fraction multiplied by the denominator of the first fraction (CHAPTER 4 FLASHCARDS)
(See page 106 in your textbook.)
cube  a 3-dimensional figure that contains six square faces; at each vertex, all sides meet at right angles (CHAPTER 9 FLASHCARDS)
(See page 249 in your textbook.)
cubic units  the units of measure used with volume, such as cubic inches or cubic meters (CHAPTER 9 FLASHCARDS)
(See page 252 in your textbook.)
customary units of measure  the system of measurement used in the United States; includes inches, feet, and miles for distance and ounces, pounds, and tons for weight (CHAPTER 7 FLASHCARDS)
(See page 183 in your textbook.)
cylinder  a 3-dimensional figure that has both a circular base and a circular top, and whose height is the perpendicular distance from the top to the bottom (CHAPTER 9 FLASHCARDS)
(See page 250 in your textbook.)
data  numerical information (CHAPTER 8 FLASHCARDS)
(See page 197 in your textbook.)
decimal  a fraction in which the whole is divided into tenths, hundredths, thousandths, ten-thousandths, and so on
(See page 75 in your textbook.)
degree  the unit of measurement for angles; one degree is 1/360 of a circle (CHAPTER 9 FLASHCARDS)
(See page 224 in your textbook.)
denominator  the bottom number in a fraction (CHAPTER 4 FLASHCARDS)
(See page 103 in your textbook.)
diameter  the distance across a circle through the center (CHAPTER 9 FLASHCARDS)
(See page 232 in your textbook.)
difference  the answer to a subtraction problem (CHAPTER 1 FLASHCARDS)
(See page 21 in your textbook.)
digit  one of the ten number symbols (0, 1, 2, 3, 4, 5, 6, 7, 8, and 9) (CHAPTER 1 FLASHCARDS)
(See page 17 in your textbook.)
distributive property  when multiplying a number by a sum or a difference, you may first multiply each number in the sum or difference, or you can first find the sum or difference and then multiply; for any numbers a, b, and c, a(b + c) = ab + ac and a(b – c) = ab – ac (CHAPTER 1 FLASHCARDS)
(See pages 41 and 293 in your textbook.)
dividend  the number that is divided in a division problem (CHAPTER 1 FLASHCARDS)
(See page 22 in your textbook.)
divisor  the number that goes into another number in a division problem (CHAPTER 1 FLASHCARDS)
(See page 22 in your textbook.)
equation  a statement showing that two amounts are equal (CHAPTER 10 FLASHCARDS)
(See page 294 in your textbook.)
equilateral triangle  a triangle with three equal sides and three equal angles, each measuring 60° (CHAPTER 9 FLASHCARDS)
(See page 259 in your textbook.)
estimate  (noun) an approximate value; (verb) to find an approximate value (CHAPTER 1 FLASHCARDS)
(See page 25 in your textbook.)
evaluating  substituting a value for the variable in an algebraic expression and solving (CHAPTER 10 FLASHCARDS)
(See page 292 in your textbook.)
even number  a whole number that is evenly divisible by 2 (CHAPTER 1 FLASHCARDS)
(See page 19 in your textbook.)
exponent  a number that tells the power to which a base is raised (for example, in 32 the base is 3 and the exponent is 2) (CHAPTER 1 FLASHCARDS)
(See page 32 in your textbook.)
factor  (noun) a number or variable that divides evenly into another number or algebraic expression; (verb) to write a number or an algebraic expression as a product of two or more terms (CHAPTER 1 FLASHCARDS, CHAPTER 11 FLASHCARDS)
(See pages 20 and 339 in your textbook.)
formula  a mathematical rule that tells the relationship between quantities
(See page 67 in your textbook.)
fraction  a part of a whole (CHAPTER 4 FLASHCARDS)
(See page 103 in your textbook.)
geometry  the branch of mathematics that studies points, lines, angles, surfaces, and solid figures (CHAPTER 9 FLASHCARDS)
(See page 223 in your textbook.)
gram  the standard unit of weight in the metric system (CHAPTER 7 FLASHCARDS)
(See page 186 in your textbook.)
graph  a diagram that shows a relationship among numbers (CHAPTER 8 FLASHCARDS)
(See page 197 in your textbook.)
grouping symbols  symbols such as parentheses or the fraction bar that tell which operations to do first (CHAPTER 1 FLASHCARDS)
(See page 44 in your textbook.)
horizontal axis  the line that usually runs along the bottom of a graph; the x-axis on the coordinate plane (CHAPTER 8 FLASHCARDS)
(See page 201 in your textbook.)
horizontal line  a line that runs from left to right (CHAPTER 9 FLASHCARDS)
(See page 223 in your textbook.)
hypotenuse  in a right triangle, the side opposite (across from) the right angle (CHAPTER 9 FLASHCARDS)
(See page 259 in your textbook.)
improper fraction  a fraction in which the numerator is greater than or equal to the denominator (CHAPTER 4 FLASHCARDS)
(See page 103 in your textbook.)
inequality  a statement showing that two amounts are not equal; the symbols are < (less than), > (greater than), ≤ (less than or equal to), and ≥ (greater than or equal to) (CHAPTER 10 FLASHCARDS)
(See page 304 in your textbook.)
intercept  the coordinates of the point where a line crosses the x-axis or y-axis of the coordinate plane (CHAPTER 11 FLASHCARDS)
(See page 332 in your textbook.)
intersection  the point where two lines or line segments meet (CHAPTER 9 FLASHCARDS)
(See page 224 in your textbook.)
isosceles triangle  a triangle in which two sides have the same length; the two angles opposite the equal sides have the same measure (CHAPTER 9 FLASHCARDS)
(See page 259 in your textbook.)
legs  the two shorter sides in a right triangle (CHAPTER 9 FLASHCARDS)
(See page 259 in your textbook.)
like fractions  fractions with the same denominator (CHAPTER 4 FLASHCARDS)
(See page 115 in your textbook.)
line  a straight path of points that continues in two opposite directions (CHAPTER 9 FLASHCARDS)
(See page 223 in your textbook.)
line segment  a straight path of points with definite length, having two endpoints (CHAPTER 9 FLASHCARDS)
(See page 223 in your textbook.)
linear equation  an equation whose graph is a straight line (CHAPTER 11 FLASHCARDS)
(See page 329 in your textbook.)
liter  the standard unit of liquid measure in the metric system (CHAPTER 7 FLASHCARDS)
(See page 186 in your textbook.)
lowest terms  the status of a fraction that cannot be reduced further (CHAPTER 4 FLASHCARDS)
(See page 104 in your textbook.)
mean  the sum of a set of numbers divided by the number of numbers in a set; another name for average (CHAPTER 1 FLASHCARDS, CHAPTER 8 FLASHCARDS)
(See pages 30, 67, and 217 in your textbook.)
median  a number in the middle of a set of numbers, or the mean of the two middle numbers in a set (CHAPTER 1 FLASHCARDS, CHAPTER 8 FLASHCARDS)
(See pages 31 and 217 in your textbook.)
meter  the standard unit of length in the metric system (CHAPTER 7 FLASHCARDS)
(See page 186 in your textbook.)
metric system  the system of measurement used in most countries; includes meters and kilometers for distance and grams and kilograms for weight (CHAPTER 7 FLASHCARDS)
(See page 183 in your textbook.)
mixed number  a number with both a whole number and a fraction (CHAPTER 4 FLASHCARDS)
(See page 104 in your textbook.)
mode  the most frequently occurring number in a set (CHAPTER 8 FLASHCARDS)
(See page 217 in your textbook.)
monomial  an algebraic expression with only one letter, number, or group of letters and numbers not separated by plus or minus signs (for example, 5x) (CHAPTER 11 FLASHCARDS)
(See page 336 in your textbook.)
negative number  a number less than zero (CHAPTER 10 FLASHCARDS)
(See page 281 in your textbook.)
number line  a line used to represent positive numbers, negative numbers, and zero (CHAPTER 10 FLASHCARDS)
(See page 281 in your textbook.)
number sequence  a list of numbers in a special order or pattern (for example, 2, 4, 6, 8, 10…); also called a number series (CHAPTER 1 FLASHCARDS)
(See page 36 in your textbook.)
numerator  the top number in a fraction (CHAPTER 4 FLASHCARDS)
(See page 103 in your textbook.)
obtuse angle  an angle that measures more than 90° and less than 180° (CHAPTER 9 FLASHCARDS)
(See page 225 in your textbook.)
odd number  a whole number that is not evenly divisible by 2 (CHAPTER 1 FLASHCARDS)
(See page 19 in your textbook.)
opposite sides  sides in a quadrilateral that are across from each other (CHAPTER 9 FLASHCARDS)
(See page 232 in your textbook.)
origin  the point on the coordinate plane where the x-axis and the y-axis intersect (CHAPTER 11 FLASHCARDS)
(See page 323 in your textbook.)
parabola  the curve formed by the graph of a quadratic equation (CHAPTER 11 FLASHCARDS)
(See page 347 in your textbook.)
parallel lines  lines that run in the same direction and do not cross (CHAPTER 9 FLASHCARDS)
(See page 224 in your textbook.)
parallelogram  a four-sided figure with two pairs of parallel sides (CHAPTER 9 FLASHCARDS)
(See page 232 in your textbook.)
percent  a fraction in which the whole is divided into 100 parts; the symbol is %
(See page 149 in your textbook.)
perfect square  a number that has an exact square root (for example, √81 = 9) (CHAPTER 11 FLASHCARDS)
(See page 341 in your textbook.)
perimeter  the distance around a closed plane figure (CHAPTER 9 FLASHCARDS)
(See page 234 in your textbook.)
perpendicular lines  lines that intersect at a right angle (CHAPTER 9 FLASHCARDS)
(See page 224 in your textbook.)
pi  the Greek letter π representing the ratio of the circumference of a circle to its diameter; the approximate value is 3.14, or 22/7 (CHAPTER 9 FLASHCARDS)
(See page 232 in your textbook.)
place value  the number that a digit stands for (for example, in 35.6, the digit 3 stands for 30 because 3 is in the tens place. The digit 6 stands for 6/10 because 6 is in the tenths place) (CHAPTER 1 FLASHCARDS)
(See page 17 in your textbook.)
plane  a flat surface (CHAPTER 9 FLASHCARDS)
(See page 231 in your textbook.)
point  a fixed position in space (CHAPTER 9 FLASHCARDS)
(See page 223 in your textbook.)
polygon  a closed plane figure formed by three or more line segments that meet only at their endpoints (CHAPTER 9 FLASHCARDS)
(See page 231 in your textbook.)
positive number  a number greater than zero (CHAPTER 1 FLASHCARDS, CHAPTER 10 FLASHCARDS)
(See pages 19 and 281 in your textbook.)
power  a product of identical factors (for example, 32, or "3 to the second power", means 3 x 3 x 3; the base is 3 and the exponent is 2) (CHAPTER 1 FLASHCARDS)
(See page 32 in your textbook.)
prime number  a number that is evenly divisible only by itself and 1 (CHAPTER 1 FLASHCARDS)
(See pages 20 and 339 in your textbook.)
probability  the chance of an event happening, usually expressed as the ratio of the number of favorable outcomes to the total number of outcomes (CHAPTER 8 FLASHCARDS)
(See pages 197 and 212 in your textbook.)
product  the answer to a multiplication problem (CHAPTER 1 FLASHCARDS)
(See pages 19 and 21 in your textbook.)
projection  a prediction based on past and current trends (CHAPTER 8 FLASHCARDS)
(See page 205 in your textbook.)
proper fraction  a fraction in which the numerator is less than the denominator (CHAPTER 4 FLASHCARDS)
(See page 103 in your textbook.)
proportion  a statement showing that two ratios (or fractions) are equal
(See page 140 in your textbook.)
protractor  a tool for measuring and drawing the degrees in an angle (CHAPTER 9 FLASHCARDS)
(See page 226 in your textbook.)
Pythagorean relationship  for a right triangle, the square of the hypotenuse is equal to the sum of the squares of the other two sides; the formula is a2 + b2 = c2, where a and b are the legs of a right triangle and c is the hypotenuse (CHAPTER 9 FLASHCARDS)
(See page 271 in your textbook.)
quadratic equation  an equation in which at least one variable is raised to the second power (CHAPTER 11 FLASHCARDS)
(See page 346 in your textbook.)
quadrilateral  a closed figure with four sides (CHAPTER 9 FLASHCARDS)
(See page 232 in your textbook.)
quotient  the answer to a division problem (CHAPTER 1 FLASHCARDS)
(See pages 22, 88, and 123 in your textbook.)
radius  the distance from the center of a circle to its circumference; the distance from any point on the surface of a sphere to the center (CHAPTER 9 FLASHCARDS)
(See pages 232 and 250 in your textbook.)
ratio  a comparison of two numbers by division; may be written with a colon (:), as a fraction, or with the word to
(See page 137 in your textbook.)
ray  a straight path of points that begins at one point and continues in one direction (CHAPTER 9 FLASHCARDS)
(See page 223 in your textbook.)
reciprocal  an inverted fraction (for example, 2/3 inverted is 3/2) (CHAPTER 4 FLASHCARDS)
(See page 123 in your textbook.)
rectangle  a four-sided figure with four right angles and with two pairs of parallel sides (CHAPTER 9 FLASHCARDS)
(See page 232 in your textbook.)
rectangular solid  a 3-dimensional figure in which each face is a rectangle (CHAPTER 9 FLASHCARDS)
(See page 250 in your textbook.)
reducing  expressing a fraction in lowest terms (CHAPTER 4 FLASHCARDS)
(See page 104 in your textbook.)
reflex angle  an angle that measures more than 180° and less than 360° (CHAPTER 9 FLASHCARDS)
(See page 225 in your textbook.)
rhombus  a four-sided figure with four equal sides (CHAPTER 9 FLASHCARDS)
(See page 232 in your textbook.)
right angle  an angle that measures exactly 90° (CHAPTER 9 FLASHCARDS)
(See page 225 in your textbook.)
right triangle  a triangle with one right angle (CHAPTER 9 FLASHCARDS)
(See page 259 in your textbook.)
round number  a number that ends in zero or zeros (CHAPTER 1 FLASHCARDS)
(See page 24 in your textbook.)
rounding  making an estimate that is close to an original amount (CHAPTER 1 FLASHCARDS)
(See page 24 in your textbook.)
scalene triangle  a triangle with no equal sides and no equal angles (CHAPTER 9 FLASHCARDS)
(See page 259 in your textbook.)
scientific notation  a number written as the product of a number between 1 and 10 and a power of 10
(See pages 93 and 127 in your textbook.)
similar figures  geometric figures with the same shape but not necessarily the same size (CHAPTER 9 FLASHCARDS)
(See page 263 in your textbook.)
simplifying  reducing a ratio or combining like terms in an algebraic expression
(See page 137 in your textbook.)
sine  for an acute angle in a right triangle, the ratio of the opposite side to the hypotenuse; abbreviated as sin (CHAPTER 11 FLASHCARDS)
(See page 343 in your textbook.)
slope  a measure of the "steepness" of a line on the coordinate plane; defined as the change in y values divided by the change in x values (CHAPTER 11 FLASHCARDS)
(See page 331 in your textbook.)
solid  a 3-dimensional figure (CHAPTER 9 FLASHCARDS)
(See page 249 in your textbook.)
sphere  a 3-dimensional figure each point of which is an equal distance from the center (CHAPTER 9 FLASHCARDS)
(See page 250 in your textbook.)
square  in geometry, a four-sided figure with four right angles, four equal sides, and two pairs of parallel sides (CHAPTER 9 FLASHCARDS)
(See page 232 in your textbook.)
square pyramid  a 3-dimensional figure whose base is a square and each of whose four triangular faces meet at a common point (CHAPTER 9 FLASHCARDS)
(See page 250 in your textbook.)
square root  one of two equal factors of a number; the symbol is √ (CHAPTER 1 FLASHCARDS)
(See page 34 in your textbook.)
square units  the units of measure used with area, such as square inches, square feet, and square meters (CHAPTER 9 FLASHCARDS)
(See page 240 in your textbook.)
statistics  the study of organizing and interpreting data (CHAPTER 8 FLASHCARDS)
(See page 197 in your textbook.)
straight angle  an angle that measures exactly 180° (CHAPTER 9 FLASHCARDS)
(See page 225 in your textbook.)
subscripts  small numbers appearing at the lower right-hand corner of a variable to refer to the different values of the variable in a formula (for example, x1 + x2 + xn)
(See page 67 in your textbook.)
sum  the answer to an addition problem (CHAPTER 1 FLASHCARDS)
(See pages 18 and 21 in your textbook.)
supplementary angles  angles whose sum is 180° (CHAPTER 9 FLASHCARDS)
(See page 228 in your textbook.)
table  an organized chart or list of numbers (CHAPTER 8 FLASHCARDS)
(See pages 197 and 209 in your textbook.)
tangent  for an acute angle in a right triangle, the ratio of the opposite side to the adjacent side; abbreviated as tan (CHAPTER 11 FLASHCARDS)
(See page 343 in your textbook.)
transversal  a line that cuts across parallel lines, intersecting each of them (CHAPTER 9 FLASHCARDS)
(See page 229 in your textbook.)
trapezoid  a four-sided figure with one pair of parallel sides (CHAPTER 9 FLASHCARDS)
(See page 232 in your textbook.)
triangle  a closed plane figure with three sides and three angles (CHAPTER 9 FLASHCARDS)
(See pages 231 and 259 in your textbook.)
trigonometry  the study of the relationship between pairs of sides in right triangles (CHAPTER 11 FLASHCARDS)
(See page 343 in your textbook.)
unknown  a quantity of undetermined numerical value, usually represented by a letter (CHAPTER 10 FLASHCARDS)
(See page 292 in your textbook.)
unlike fractions  fractions with different denominators (CHAPTER 4 FLASHCARDS)
(See page 116 in your textbook.)
variable  a letter that can be replaced by numbers (CHAPTER 10 FLASHCARDS)
(See pages 281 and 292 in your textbook.)
vertex  the point where two sides of a closed figure or two sides of an angle meet (CHAPTER 9 FLASHCARDS)
(See pages 224, 232, and 250 in your textbook.)
vertical angles  two equal angles that lie across from each other when two lines intersect (CHAPTER 9 FLASHCARDS)
(See page 229 in your textbook.)
vertical axis  the line that runs up and down one side of a graph; the y-axis on the coordinate plane (CHAPTER 8 FLASHCARDS, CHAPTER 9 FLASHCARDS)
(See page 201 in your textbook.)
vertical line  a line that runs up and down (CHAPTER 9 FLASHCARDS)
(See page 223 in your textbook.)
volume  the amount of space inside a 3-dimensional figure; usually measured in cubic units (CHAPTER 9 FLASHCARDS)
(See page 252 in your textbook.)
x-axis  the horizontal line that divides the coordinate plane (CHAPTER 11 FLASHCARDS)
(See page 323 in your textbook.)
y-axis  the vertical line that divides the coordinate plane (CHAPTER 11 FLASHCARDS)
(See page 323 in your textbook.)
whole number  a number that is evenly divisible by 1 (CHAPTER 1 FLASHCARDS)
(See pages 17 and 19 in your textbook.)