Prentice Hall Geometry

Table 4 Properties of Real Numbers

Unless otherwise stated, a, b, c, and d represent real numbers.

Identity Properties
Addition eh plus . 0 equals eh and 0 plus . eh equals eh
Multiplication eh middle dot . 1 equals eh and 1 middle dot . eh equals eh
Commutative Properties
Addition eh plus , b equals . b plus eh
Multiplication eh middle dot , b equals . b middle dot eh
Associative Properties
Multiplication open eh plus b close . plus , c equals , eh plus . open b plus c close
Addition open eh middle dot b close . middle dot , c equals , eh middle dot . open b middle dot c close
Inverse Properties
Addition The sum of a number and its opposite, or additive inverse, is zero.
eh plus . open negative eh close . equals 0 and negative , eh plus . eh equals 0
Multiplication The reciprocal, or multiplicative inverse, of a rational number eh over b is b over eh , open eh comma b , not equal to 0 close .
eh middle dot , 1 over eh , equals 1 and 1 over eh , middle dot , eh equals . 1 open eh not equal to 0 close
Distributive Properties
eh open b plus c close . equals eh b . plus eh c open b plus c . close eh equals b eh . plus c eh
eh open b minus c close . equals eh b . negative eh c open b minus c . close eh equals b eh . negative c eh
Properties of Equality
Addition If eh equals b comma then eh plus , c equals . b plus c .
Subtraction If eh equals b comma then eh minus , c equals . b minus c .
Multiplication If eh equals b comma then eh middle dot , c equals . b middle dot c .
Division If eh equals b and c not equal to 0 comma then eh over c , equals , b over c . .
Substitution If eh equals b comma then b can replace a in any expression.
Reflexive eh equals eh
Symmetric If eh equals b comma then b equals eh , .
Transitive If eh equals b and b equals c comma then eh equals c .
Properties of Proportions
eh over b , equals , c over d . open eh comma b comma c comma d , not equal to 0 close is equivalent to
  1. eh d equals b c
  2. b over eh , equals , d over c
  3. eh over c , equals , b over d
  4. fraction eh plus b , over b end fraction . equals . fraction c plus d , over d end fraction
Zero-Product Property
If eh b equals 0 comma then eh equals 0 or b equals 0 , .
Properties of Inequality
Addition If eh greater than b and c greater than or equal to d comma then eh plus , c greater than . b plus d .
Multiplication If eh greater than b and c greater than 0 comma then eh c greater than b c . .
  If eh greater than b and c less than 0 comma then eh c less than b c . .
Transitive If eh greater than b and b greater than c comma then eh greater than c , .
Comparison If eh equals . b plus c comma and c greater than 0 comma then eh greater than b , .
Properties of Exponents
For any nonzero numbers a and b, any positive number c, and any integers m and n,
Zero Exponent eh to the , equals 1
Negative Exponent eh super negative n end super , equals , fraction 1 , over eh to the n end fraction
Product of Powers eh to the m , middle dot , eh to the n , equals . eh super m plus n end super
Quotient of Powers fraction eh to the m , over eh to the n end fraction . equals . eh super m minus n end super
Power to a Power open , c to the m . close to the n , equals , c super m n end super
Product to a Power open eh b , close to the n . equals , eh to the n , b to the n
Quotient to a Power open , eh over b , close to the n . equals . fraction eh to the n , over b to the n end fraction
Properties of Square Roots
For any nonnegative numbers a and b, and any positive number c,
Product of Square Roots square root of eh dot square root of b equals , square root of eh b end root
Quotient of Square Roots fraction square root of eh , over square root of c end fraction , equals , square root of eh over c end root

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Table of Contents

Prentice Hall Geometry Chapter 1 Tools of Geometry Chapter 2 Reasoning and Proof Chapter 3 Parallel and Perpendicular Lines Chapter 4 Congruent Triangles Chapter 5 Relationships Within Triangles Chapter 6 Polygons and Quadrilaterals Chapter 7 Similarity Chapter 8 Right Triangles and Trigonometry Chapter 9 Transformations Chapter 10 Area Chapter 11 Surface Area and Volume Chapter 12 Circles Skills Handbook Reference Visual Glossary Selected Answers Index Acknowledgments