Download 3x – 4 = 7

Unit3 #1
Name:______KEY___________________
Introduction to Algebra: Vocabulary
Equation: a math sentence that states two quantities are equal .
It will have an equal sign .
3x – 4 = 7
The equation says: what is on the left (
3x – 4
) is equal to what is on the right (
7 ).
Parts of an Equation
Variable: a letter that represents a number we do not know yet.
3x – 4 = 7
!!! Every variable has a coefficient
Coefficient: the number _multiplied by_ the variable. Can be
_positive_ or _negative__ .
Constant: a real number with no _variable_ attached.
Term – any of the following:
single number (constant)
single variable
the product of a number (coefficient) and variable(s).
What coefficient
does this variable
have? -1
2k + 15 – m – 3 + n – 7p
– 8 – 4c + 7 – c – 12c – 2
Terms: __2k, 15, −m, −3, n, p___
Terms: __−8, −4c, 7, −c, −12c, −2 __
Variables: _k, m, n, p____
Variables: __c________________
Coefficients: _2, −1, 1, −7__
Coefficients: _−4, −1, −12__
Constants: __15, −3____
Constants: __−8, 7, −2____
EXPRESSION: a group of terms. Contains numbers, operational signs, and variables.
DOES NOT contain an _equal sign__ .
Label the parts of the expression: Coefficient, Constant, Variable
1.
8y – 7 + 2y
Coefficient
Variable
Constant
How many TERMS are present in this expression? _3_ List them: __8y, −7, 2y____
2.
m + 4 + 2 – 7m + 6
How many TERMS are present in this expression? ____ List them: ___________________________
Identify the terms, variables, coefficients, and constants in each expression.
3. –4a – 7b + 5 + c
4. 7 – 5h – 2 – k
Terms:
Terms:
Variables:
Variables:
Coefficients:
Coefficients:
Constants:
Constants:
5. 5 – 4x – 8y
6. 9k + 7 – k + 4
Terms:
Terms:
Variables:
Variables:
Coefficients:
Coefficients:
Constants:
Constants:
Inequality – a mathematical sentence that contains the symbols: _<_ _>_ _≤_ _≥_ .
>: __is greater than____
< : __is less than___
≥: _is greater than or equal to_
≤ : _ is less than or equal to _
Tell whether the following phrases are expressions, equations, or inequalities. Circle the key symbol.
1) 5x > 25
inequality
2)
–2
expression
3) 29 – k
expression
4) 8b + 9c < 45
inequality
5)
6) r – (–12) = 9
equation
7) –4m = 16
8) h + (–9) ≥ 3
Write without parentheses (Simplify the expressions):
(–a) · 3
(–5) · x
(–1) · (–c)
–8 · (–m)
(−1) · a · 3 = −3 · a = −3a
−5x
(–1) · (–1) · c = 1c = c
8m
4 · (–b)
–(–8) · y
(–d) · (–6)
(–n) · (–7)
−4b
8y
6d
(–3) · 2x
–3 · 2x
3 · (–2x)
(–3) · (–2x)
(–3) · 6a
(–7x) · (–5)
–8m · 3
–6 · (–2d)
6a ÷ 2
–6a ÷ 2
6a ÷ (–2)
(–6a) ÷ (–2)
(−3 · 2) · x = −6x
(6 ÷ 2)a = 3a
Label the following parts.
Math
Sentence
Variables
Coefficients
Constants
# of Terms
Equation,
Expression, or
Inequality?