# Operation on Real Numbers Contributed by: The real number, in mathematics, is a quantity that can be expressed as an infinite decimal expansion. The real numbers include the positive and negative integers and fractions (or rational numbers) and also the irrational numbers.
1. Intermediate Algebra – 1.3
• Operations with
Real Numbers
2. Three people
were at work on a
construction site. All
were doing the same
job, but when each was
3. “Breaking rocks,” the first
replied. “Earning my living,” the
second said.”Helping to build a
cathedral,” said the third.” – Peter
• Adding numbers with the same sign
• To add two numbers that have
absolute values and keep the
same sign
signs
• To add two numbers that have
different signs, subtract their
absolute values and keep the sign
of the number with the greater
absolute value.
6. Procedure - Subtraction
• For any real number a
• a – b = a + (-b)
7. Distance on number line
• The distance between two
points a and b is
• d = |a – b| = |b – a|
8. Procedure - Multiplying
• When multiplying two real
numbers that have different
signs, the product is negative
9. Procedure - Multiplying
• When multiplying two numbers that have
the same sign, the product is positive
10. Procedure - multiplying
• The product of an even number
of negative factors is positive,
• The product of an odd number
of negative factors is negative.
11. Division
• Division by Zero is undefined.
• 4/0 is undefined
• 0/4 = 0
12. a
Procedure - Division
a a a
 
b b b
13. Definition Square Root
• For all real numbers a and b, if
2
b a then b is a
square root of a
• The number or expression
2 x 3
• The index is n
n
a
3
x
b
16. Calculator Keys
• [+], [*], [/], [-], [^]
• [ENTER] [2ND][ENTRY]
• [2ND] [QUIT] [x,t,n]
• [MODE]
• [MATH][NUM][1:abs( ]
17. Norman Vincent Peale:
• “What seems impossible one
minute becomes, …, possible
the next.
18. Section 1.4
• Intermediate Algebra
• Properties of Real numbers
(9)
• a+b=b+a
• 2+3=3+2
20. Commutative for
Multiplication
• ab = ba
• a + (b + c) = (a + b) + c
• 2 + (3 + 4) = (2 + 3) + 4
22. Associative for Multiplication
• (ab)c = a(bc)
• (2 x 3) x 4 = 2 x (3 x 4)
23. Distributive
• a(b + c) = ab + ac
• 2(3 + 4) = 2 x 3 + 2 x 4
• X(Y + Z) = XY +XZ
25. Multiplicative Identity
• a(1/a) = 1 where a not equal to 0
• 3(1/3) = 1
27. George Simmel - Sociologist
• “He is educated who
knows how to find out
what he doesn’t know.”
28. Section 1.4
Intermediate Algebra
• Apply order of operations
• Please Excuse My Dear Aunt
Sally.
• P – E – M – D – A- S
29. The order of operations
• Perform within grouping symbols – work
innermost group first and then outward.
• Evaluate exponents and roots.
• Perform multiplication and division left to
right.
• Perform addition and subtraction left to
right.
30. Grouping Symbols
• Parentheses
• Brackets
• Braces
• Fraction symbols – fraction bar
• Absolute value
31. Algebraic Expression
• Any combination of numbers, variables,
grouping symbols, and operation symbols.
• To evaluate an algebraic expression, replace
each variable with a specific value and then
perform all indicated operations.
32. Evaluate Expression by
Calculator
• Plug in
• Use store feature
• Use Alpha key for formulas
• Table
• Program - evaluate
33. The Pythagorean Theorem
• In a right triangle, the sum of the square of
the legs is equal to the square of the
hypotenuse.
2 2 2
a  b c
34. Equation
• A statement that two expression
have the same value
35. Intermediate Algebra – 1.5
• Walt Whitman – American Poet
• “Seeing, hearing, and
feeling are miracles,
and each part and tag
of me is a miracle.”
36. 1.5 – Simplifying Expressions
• Term – An expression that is separated by
• Numerical coefficient – the numerical
factor in a term
• Like Terms – Variable terms that have the
same variable(s) raised to the same
exponential value
37. Combining Like Terms
• To combine like terms, add or
subtract the coefficients and
keep the variables and their
exponents the same.
38. example
7  3  4   x  2   7  3 4  x  2
 11  3x
39. H. Jackson Brown Jr. Author
• “Let your
performance do the
thinking.”
40. Integer Exponents
• For any real number b and any natural
number n, the nth power of b o if found by
multiplying b as a factor n times.
n
b b b b  b
N times
41. Exponential Expression – an
expression that involves
exponents
• Base – the number being multiplied
• Exponent – the number of factors of the
base.
42. Calculator Key
^
• Exponent Key
43. Sydney Harris:
• “When I hear somebody
sigh,’Life is hard”, I am
“Compared to what?”
44. Intermediate Algebra 1.5
• Introduction
• To
• Linear Equations
45. Def: Equation
• An equation is a
statement that two
algebraic expressions
have the same value.
46. Def: Solution
• Solution: A replacement for the
variable that makes the equation
true.
• Root of the equation
• Satisfies the Equation
• Zero of the equation
47. Def: Solution Set
• A set containing all the
solutions for the given
equation.
• Could have one, two, or many elements.
• Could be the empty set
• Could be all Real numbers
48. Def: Linear Equation in One
Variable
• An equation that can be written in
the form ax + b = c where a,b,c are
real numbers and a is not equal to
zero
49. Linear function
• A function of form
• f(x) = ax + b where a and b
are real numbers and a is not
equal to zero.
50. Def: Identity
• An equation is an identity if every
permissible replacement for the variable is a
solution.
• The graphs of left and right sides coincide.
• The solution set is R
R
51. Def: Inconsistent equation
• An equation with no solution is an
inconsistent equation.
• The graphs of left and right sides never
intersect.
• The solution set is the empty set.

52. Def: Equivalent Equations
• Equivalent equations are equations that
have exactly the same solutions sets.
• Examples:
• 5 – 3x = 17
• -3x= 12
• x = -4
• If a = b, then a + c = b + c
• For all real numbers a,b, and c.
• Equals plus equals are equal.
54. Multiplication Property of
Equality
• If a = b, then ac = bc is true
• For all real numbers a,b, and c
where c is not equal to 0.
• Equals times equals are equal.
55. Solving Linear Equations
• Simplify both sides of the equation as
needed.
– Distribute to Clear parentheses
– Clear fractions by multiplying by the LCD
– Clear decimals by multiplying by a power of 10
determined by the decimal number with the
most places
– Combine like terms
56. Solving Linear Equations Cont:
• Use the addition property so that all variable
terms are on one side of the equation and all
constants are on the other side.
• Combine like terms.
• Use the multiplication property to isolate the
variable
• Verify the solution
57. Ralph Waldo Emerson – American essayist,
poet, and philosopher (1803-1882)
• “The world looks like a
multiplication table or a
mathematical equation,
which, turn it how you
will, balances itself.”
58. Problem Solving 1.6
• 1. Understand the Problem
• 2. Devise a Plan
– Use Definition statements
• 3. Carry out a Plan
• 4. Look Back
– Check units
59. Types of Problems
• Number Problems
• Angles of a Triangle
• Rectangles
• Things of Value
60. Les Brown
• “If you view all the things
that happen to you, both
opportunities, then you
operate out of a higher level
of consciousness.”
61. Types of Problems Cont.
• Percentages
• Interest
• Mixture
• Liquid Solutions
• Distance, Rate, and Time
62. Albert Einstein
• “In the middle of
difficulty lies
opportunity.”
63. Ralph Waldo Emerson – American essayist,
poet, and philosopher (1803-1882)
• “The world looks like a
multiplication table or a
mathematical equation,
which, turn it how you
will, balances itself.”
64. Section 1.8
• Solve Formulas
• Isolate a particular variable in a formula
• Treat all other variables like constants
• Isolate the desired variable using the outline
for solving equations.
65. Know Formulas
• Area of a rectangle
A = LW
• Perimeter of a rectangle
• P = 2L + 2W
66. Formulas continued
• Area of a square
2
A s
• Perimeter of a square
P 4 s
67. Formulas continued
• Area of Parallelogram
•A = bh
68. Formulas continued
• Trapezoid
1
A   b1  b2  h
2
69. Formulas continued
• Area of Circle
2
A  r
• Circumference of Circle
C 2 r C  d
70. Formulas continued:
• Area of Triangle
1
A  bh
2
71. Formulas continued
• Sum of measures of a triangle
o
m1  m2  m3 180
72. Formulas continued
• Perimeter of a Triangle
P s1  s2  s3
73. Formulas continued
• Pythagorean Theorem
2 2 2
a  b c
74. Formulas continued:
• Volume of a Cube – all sides are equal
3
V s
75. Formulas continued
• Rectangular solid
V lwh
• Area of Base x height
76. Formulas continued
• Volume Right Circular Cylinder
2
V  r h
77. Formulas continued:
• Surface are of right circular cylinder
2
S 2 rh  2 r
78. Formulas continued:
• Volume of Right Circular Cone
• V=(1/3) area base x height
1 2
V  r h
3
79. Formulas continued:
• Volume Sphere
4 3
V  r
3
80. Formulas continued:
• General Formula surface area right solid
• SA = 2(area base) + Lateral surface area
• SA=2(area base) + LSA
• Lateral Surface Area = LSA =
• (perimeter)*(height)
81. Formulas continued:
• Distance, rate and Time
d = rt
Interest
I = PRT
82. Useful Calculator Programs
• CIRCLE
• CIRCUM
• CONE
• CYLINDER
• PRISM
• PYRAMID
• TRAPEZOI
• APPS-AreaForm
83. Robert Schuller – religious leader
• “Spectacular achievement
is always preceded by
spectacular preparation.”