Download 5 + 84 Numerical 3x + 10 Algebraic

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An expression is NOT an equation
because it DOES NOT have an equal sign.
There are 2 types of expressions.
5 + 84 Numerical
3x + 10 Algebraic
Notice there are no equal signs in these
expressions so they are not equations!
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1
A numerical expression contains only
numbers and symbols and NO LETTERS.
5 times 3 plus 8
(5•3) + 8
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An algebraic expression contains
only numbers, symbols, and
variables. It is sometimes referred
to as a variable expression.
The product of 3 and x
The sum of m and 8
The difference of r and 2
3x
m+8
r-2
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2
What is a variable?
A variable represents an unknown value.
1) 4 + x
2) 10 –
3) 5y
4) 20
?
A variable can be any letter of the
alphabet since it represents an unknown.
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Word Phrases for multiplication are:
The product of 5 and a number c
5 • c or 5c
Seven times a number t
7 • t or 7t
6 multiplied by a number d
6 • d or 6d
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3
The Placement rule for multiplication is:
The product of 5 and a number c
5 • c or 5c
Seven times a number t
7 • t or 7t
6 multiplied by a number d
Always
write the
variable
AFTER the
number.
6 • d or 6d
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Evaluate means to find the value of an
algebraic expression by substituting
numbers in for variables.
m=2
6+m?
6+2
8
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4
Evaluate means to find the value of an
algebraic expression by substituting
numbers in for variables.
r=3
7+r?
7+3
10
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Evaluate the variable expression when n = 6.
1) n + 8
2) n − 2
6+8
6−2
4
14
Evaluate just means solve by substitution.
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5
Evaluate the variable expression when n = 6.
4) n
3) 3n
6
6
6
3•6
18
1
Evaluate just means solve by substitution.
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Evaluate the algebraic expression when n = 8.
1) 56
n
56
8
2) 20 − n
20 − 8
12
7
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6
Evaluate the expression if a = 3 and b = 4.
1) 3a + b
3• 3+ 4
9+4
13
2) 2b − a
2•4−3
8−3
5
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Evaluate the expression if a = 3 and b = 4.
3) 2ab
2 • 3• 4
6•4
4) 5 + ab
5 + 3• 4
5 + 12
17
24
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7
Evaluate the expression if x = 5 and y = 3.
3x
1)
y
2) x 2 + y 2
52 + 32
25 + 9
3•5
3
15
3
5
34
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Take Out Your Study Guide!!!
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8
#1
TYPES OF EXPRESSIONS
An expression is NOT an equation because it
does not have an equal sign. There are 2
types of expressions.
NUMERICAL EXPRESSION: Contains only numbers and
symbols. Example: 5 • 3 + 4
ALGEBRAIC EXPRESSION: Contains numbers,
symbols, and variables. Also known as a
variable expression. Example: m + 8
A VARIABLE is a letter or symbol that represents a
number. Example: x
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#2
Evaluate if x = 3 and y = 4
2 (x + y)
2
2(3 + 4)2
2(7) 2
2(49)
98
Evaluate means solve.
Show the substitution.
Show your work down.
Circle your answer.
Show your work one step at a
time down. No equal signs!
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