1.1 Introduction To Algebra Homework: Odds 1-55
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·Variable-
a letter that represents a variety of different numbers
·Constant-
a consistent value
·Algebraic
expression-
an expression consisting of variables, and/or numerals and often with
operation signs and grouping
symbols *Notice:
an expression does NOT contain an =
·Evaluating
an expression-
replacing the variable with a value and performing the computations
Example: Evaluate 
Example: Evaluate 
Graphing Calculator Exercise: Evaluate 
Translate phrases to algebraic expressions:
Phrase:
Algebraic Expression:
19 less than some
number
a number is increased by
13
the quotient of two
numbers
twice a
number
5% of a
number
4/5 of a
number
*Notice: “of” translates to multiplication in “% of” or “a
fraction of”
8 less than 5 times a
number
8 is less than 5 times a
number
*Notice: “less than” translates as subtraction, but “is less than”
translates as an inequality symbol
·Equation-
a number sentence with the verb =
*Notice: An expression does NOT have =
An equation has =
Equations can be true, false, or neither.
Examples:
(TRUE)
(FALSE)
(NEITHER, depends on
the value of x)
(TRUE for all values of
x)
(FALSE for any value of
x)
*Notice: Equations can be solved.
To solve means to find the replacement value for x that makes the
equation true (called a solution).
Example: Determine whether 13 is a solution
of 
.
We have determined that 13 is NOT a solution of the given equation.
Translate sentences to equations:
*Notice: “is” usually translates as =
Examples:
Seven times some number is
4521.
3% of some number is
13.
4 less than some number is
51.
The product of two numbers is
136.
*Notice: You do NOT have to solve the equations, just translate.
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