This document provides a lesson on identifying parts of algebraic expressions including variables, coefficients, constants, and terms. It includes examples of evaluating expressions for given variable values and finding missing values in tables. The summary evaluates the expression x ÷ 4 for x = 12 and identifies that the student made an error in subtracting instead of dividing, with the correct answer being 3.

1. Name _________________________________ Date __________________________
Mrs. Labuski / Mrs. Portsmore Period _______ Lesson 2-1 Variables & Expressions
Essential Question: How do you identify and describe parts of an expression?
VOCABULARY DEFINITION EXAMPLE
constant
variable
algebraic
expression
term
coefficient
Identify the coefficient and the variable in each algebraic expression.
1.) 4b 2.) 74x 3.) 5y

2. coefficient ________ coefficient ________ coefficient ________
variable __________ variable __________ variable __________
4.) 4x – 12 5.) a + 3b
4 is a(n) ___________________ a is a(n) ___________________
x is a(n) ___________________ 3 is a(n) ___________________
12 is a(n) __________________ b is a(n) __________________
terms: _____________________ terms: _____________________
Evaluate each expression for the given value of the variable.
6.) x + 5, for x = 6 7.) 3p, for p = 5 8.) z ÷ 4, for z = 24
________________ ________________ ________________
Evaluate each expression to find the missing values or missing expression in the tables.
n n+8 n 7n n
7 15 7 49 35 50
9 8 5 20
22 6 20 35
35 9 85 100
n 25 - n n 24 ÷ n n
20 5 2 12 13 26
5 6 9 18
18 4 30 60
9 8 25 50
Shawn evaluated the algebraic expression x ÷ 4 for x = 12 and gave an answer of 8. What was
his error? What was the correct answer?
_____________________________________________________________________________
_____________________________________________________________________________
Name _________________________________ Date __________________________
Mrs. Labuski / Mrs. Portsmore Period _______ Lesson 2-1 Variables & Expressions

3. Essential Question: How do you identify and describe parts of an expression?
VOCABULARY DEFINITION EXAMPLE
A number that is alone. It
4, 5, 6,
constant is a value that does not
(any number)
change.
A letter or symbol used to
x=6
represent a number that
variable any letter can be
we don’t know yet. The
used
value that can change.
A mathematical phrase
algebraic
that contains at least one x+2
expression
variable
the parts of an expression 3x + 4
term that are separated by a + 3x = term
or - sign 4 = term
4x is the
a number used to multiply (same as 4• x)
coefficient
a variable the “4” is the
coefficient
Identify the coefficient and the variable in each algebraic expression.
1.) 4b 2.) 74x 3.) 5y
coefficient __4______ coefficient __74______ coefficient __5______

4. variable ____b______ variable ____x______ variable ___y_______
4.) 4x – 12 5.) a + 3b
4 is a(n) ___coefficeint__________ a is a(n) __ variable
x is a(n) ___variable______________ 3 is a(n) ___ coefficeint
12 is a(n) ____constant______________ b is a(n) _____ variable
terms: __4x, 12 terms: a, 3b
Evaluate each expression for the given value of the variable.
6.) x + 5, for x = 6 7.) 3p, for p = 5 8.) z ÷ 4, for z = 24
6+5 3•5 24 ÷ 4
______11__________ _____ 15_________ ________6________
Evaluate each expression to find the missing values or missing expression in the tables.
n n+8 n 7n n n + 15
7 15 7 49 35 50
9 17 8 56 5 20
22 30 6 42 20 35
35 43 9 63 85 100
n 25 - n n 24 ÷ n n n• 2 or 2n
20 5 2 12 13 26
5 20 6 4 9 18
18 7 4 6 30 60
9 16 8 3 25 50
Shawn evaluated the algebraic expression x ÷ 4 for x = 12 and gave an answer of 8. What was
his error? What was the correct answer?
He subtracted instead of divided.
The answer should have been 3