Evaluating
Algebraic Expressions
MATHEMATICS 7
Quarter 2 Week 4
MR. CARLO JUSTINO J. LUNA
THE MATHEMATICIAN’S PRAYER
Heavenly Father, thank You for all the blessings You gave unto us.
Add joy to the world;
Subtract evil from our lives,
Multiply the good things for us.
Divide the gifts and share them to others.
Convert badness to goodness.
Help us raise our needs to You.
Extract the roots of immoralities
and perform our different functions in life.
Tell us all that life is as easy as math.
Help us all to solve our problems.
These we ask in Jesus’ name,
the greatest mathematician who ever lived on earth,
Amen!
LEARNING COMPETENCY
Evaluates algebraic expressions for given
values of the variables (M7ALIIc-4)
LEARNING OBJECTIVES
At the end of the discussion, the learners will
be able to:
• Evaluate mathematical expressions for the
given values of the variables
• Evaluate real-life algebraic expressions
SNOCANTT
A symbol that have fixed value
VOCABULARY
CONSTANT
VABLEIRA
A symbol, usually letters, which represents a value
or a number
VARIABLE
VOCABULARY
MERT
A symbol, usually a letter, used to represent any
unknown number
TERM
VOCABULARY
TENPOXEN
A small number written to the right of slightly
above another number or letter to indicate how
many times the letter or number is used as a
factor
EXPONENT
VOCABULARY
ALGAECBIR ESIONPREXS
Any combination of one or more constants and
variables along with at least one mathematical
operation
ALGEBRAIC EXPRESSION
VOCABULARY
DRILL
A
Find the answer to the following multi-operation mathematical expression by connecting
the expression in column A to the corresponding answer in column B.
𝟑 𝟖 − (𝟏𝟒 + 𝟏𝟎)
(𝟐 + 𝟔)(𝟐 − 𝟑)
𝟐 𝟑 + 𝟒 − 𝟓
𝟐 + 𝟔 𝟐 − (−𝟒)
𝟐 𝟑 /(𝟑 − 𝟏)
[𝟒 + 𝟐 + (𝟐𝟒/𝟔)] 𝟐
B
𝟓
𝟏𝟎𝟎
−𝟖
𝟑
𝟐𝟎
𝟎
REVIEW
How do we solve multi-operation
mathematical expression?
PEMDAS
Parenthesis, Exponent, Multiplication,
Division, Addition, Subtraction
MOTIVATION
SUBSTITUTION
MAPEH Integration
How do we substitute in basketball?
Activity:
Sub Me In!
Activity:
Sub Me In!
A = 1
B = 2
C = 3
D = 4
E = 5
F = 6
G = 7
H = 8
I = 9
J = 10
K = 11
L = 12
M = 13
N = 14
O = 15
P = 16
Q = 17
R = 18
S = 19
T = 20
U = 21
V = 22
W = 23
X = 24
Y = 25
Z = 26
HUMBLE 61
Activity:
Sub Me In!
A = 1
B = 2
C = 3
D = 4
E = 5
F = 6
G = 7
H = 8
I = 9
J = 10
K = 11
L = 12
M = 13
N = 14
O = 15
P = 16
Q = 17
R = 18
S = 19
T = 20
U = 21
V = 22
W = 23
X = 24
Y = 25
Z = 26
KNOWLEDGE 96
Activity:
Sub Me In!
A = 1
B = 2
C = 3
D = 4
E = 5
F = 6
G = 7
H = 8
I = 9
J = 10
K = 11
L = 12
M = 13
N = 14
O = 15
P = 16
Q = 17
R = 18
S = 19
T = 20
U = 21
V = 22
W = 23
X = 24
Y = 25
Z = 26
HARDWORK 98
Activity:
Sub Me In!
A = 1
B = 2
C = 3
D = 4
E = 5
F = 6
G = 7
H = 8
I = 9
J = 10
K = 11
L = 12
M = 13
N = 14
O = 15
P = 16
Q = 17
R = 18
S = 19
T = 20
U = 21
V = 22
W = 23
X = 24
Y = 25
Z = 26
ATTITUDE 100
VALUES Integration
What Equals 100%?
HARDWORK = 98%
KNOWLEDGE = 96%
ATTITUDE = 100%
LOVE OF GOD
= 12+15+22+5+15+6+7+15+4
= 101%
While Hard work and Knowledge will get you close,
and Attitude will get you there, it's the Love of God
that will put you over the top!
Analysis:
1. What did we do in our activity?
2. How did we find the value of the given
words?
When a number is substituted or replaced for
the variable in each algebraic expression, the
expression takes a numerical value. And
finding the value is what we call “Evaluating
the Algebraic Expression”.
Activity:
Sub Me In!
Evaluating Algebraic Expressions
- is substituting a certain number for that variable and
performs using the order of the arithmetic operations
For example:
1. If 𝑥 = 5, what is the value of 3𝑥 − 4?
2. If 𝑦 = −2 what is the value of 5𝑦 + 3?
3. If 𝑎 = 3 and 𝑏 = −6, what is the value of
2𝑎2
𝑏 − 5𝑎𝑏 + 9?
Evaluating Algebraic Expressions
There are at least two steps involved in evaluating
algebraic expression:
1. Replacing the variable by the given value
(substitution);
2. Performing the indicated arithmetic following
the order of operations.
𝒌 + 𝟗
a. 𝑘 = 𝟓 𝑘 + 9
Substitute 5 for 𝑘.
= 𝟓 + 9
Add.
= 14
Example 1: Evaluate the given algebraic expression.
𝒌 + 𝟗
b. 𝑘 = −𝟐 𝑘 + 9
Substitute −2 for 𝑘.
= −𝟐 + 9
Add.
= 7
Example 1: Evaluate the given algebraic expression.
𝟑𝒂 + 𝒃
𝑎 = 𝟓 𝑏 = 𝟒
3𝑎 + 𝑏
Substitute 5 for 𝑎 and 4 for 𝑏.
= 3(𝟓) + 𝟒
Simplify.
= 15 + 4
= 19
Example 2: Evaluate the given algebraic expression.
𝟓𝒙𝟐
+ 𝟏
𝑥 = 3
5𝑥2
+ 1
= 5(3)2
+ 1
= 5 9 + 1
= 45 + 1
= 46
Example 3: Evaluate the given algebraic expression.
𝟐𝒙𝟐
𝒚
𝒙 − 𝒚
𝑥 = 4 ; 𝑦 = 1
2𝑥2𝑦
𝑥−𝑦
=
2 4 2(1)
4−1
=
2(16)(1)
4−1
=
32
3
Example 4: Evaluate the given algebraic expression.
REAL-LIFE MATHEMATICS
DIRECTION: Use the replacement values provided to determine the cost of each
scenario.
Cactus and Succulent
No. of Cactus (c)
and succulent (s)
50c+30s Total
3 cacti and 2 succulents
4 cacti and 5 succulents
2 cacti and 6 succulents
Is Php300 enough to pay for 2 cacti and 7 succulents? Yes / No
REAL-LIFE MATHEMATICS
DIRECTION: Use the replacement values provided to determine the cost of each
scenario.
Movies
No. of tickets (t) and
popcorn (p)
200t + 100p Total
5 tickets and 3 containers
of popcorn
4 tickets and 4 containers
of popcorn
Is Php1,000 enough to pay for 4 tickets and 2
containers of popcorn?
Yes / No
NOTES
ALGEBRAIC EXPRESSION
An algebraic expression may contain
_______________ , _______________ , and one or more
_______________ .
Examples: 2𝑥 + 7
−𝑥𝑦 + 5𝑧
5𝑚2
− 3𝑚 + 1
constants operations
variables
NOTES
CONSTANT
A constant is a _______________ . Its value is always
the _______________ .
VARIABLE
A variable is a _______________ that stands for a
_______________ .
number
same
letter
number
NOTES
EVALUATING ALGEBRAIC EXPRESSION
is ___________________ a certain number for that
_________________ and performs using the order of
the arithmetic ________________.
substituting
variable
operations
Evaluating
Algebraic
Expressions
MATHEMATICS 7
Quarter 2 Week 4
SIR CJ LUNA

Evaluating Algebraic Expressions - Math 7 Q2W4 LC1

  • 1.
  • 2.
    THE MATHEMATICIAN’S PRAYER HeavenlyFather, thank You for all the blessings You gave unto us. Add joy to the world; Subtract evil from our lives, Multiply the good things for us. Divide the gifts and share them to others. Convert badness to goodness. Help us raise our needs to You. Extract the roots of immoralities and perform our different functions in life. Tell us all that life is as easy as math. Help us all to solve our problems. These we ask in Jesus’ name, the greatest mathematician who ever lived on earth, Amen!
  • 3.
    LEARNING COMPETENCY Evaluates algebraicexpressions for given values of the variables (M7ALIIc-4) LEARNING OBJECTIVES At the end of the discussion, the learners will be able to: • Evaluate mathematical expressions for the given values of the variables • Evaluate real-life algebraic expressions
  • 4.
    SNOCANTT A symbol thathave fixed value VOCABULARY CONSTANT
  • 5.
    VABLEIRA A symbol, usuallyletters, which represents a value or a number VARIABLE VOCABULARY
  • 6.
    MERT A symbol, usuallya letter, used to represent any unknown number TERM VOCABULARY
  • 7.
    TENPOXEN A small numberwritten to the right of slightly above another number or letter to indicate how many times the letter or number is used as a factor EXPONENT VOCABULARY
  • 8.
    ALGAECBIR ESIONPREXS Any combinationof one or more constants and variables along with at least one mathematical operation ALGEBRAIC EXPRESSION VOCABULARY
  • 9.
    DRILL A Find the answerto the following multi-operation mathematical expression by connecting the expression in column A to the corresponding answer in column B. 𝟑 𝟖 − (𝟏𝟒 + 𝟏𝟎) (𝟐 + 𝟔)(𝟐 − 𝟑) 𝟐 𝟑 + 𝟒 − 𝟓 𝟐 + 𝟔 𝟐 − (−𝟒) 𝟐 𝟑 /(𝟑 − 𝟏) [𝟒 + 𝟐 + (𝟐𝟒/𝟔)] 𝟐 B 𝟓 𝟏𝟎𝟎 −𝟖 𝟑 𝟐𝟎 𝟎
  • 10.
    REVIEW How do wesolve multi-operation mathematical expression? PEMDAS Parenthesis, Exponent, Multiplication, Division, Addition, Subtraction
  • 11.
  • 12.
  • 13.
    Activity: Sub Me In! A= 1 B = 2 C = 3 D = 4 E = 5 F = 6 G = 7 H = 8 I = 9 J = 10 K = 11 L = 12 M = 13 N = 14 O = 15 P = 16 Q = 17 R = 18 S = 19 T = 20 U = 21 V = 22 W = 23 X = 24 Y = 25 Z = 26 HUMBLE 61
  • 14.
    Activity: Sub Me In! A= 1 B = 2 C = 3 D = 4 E = 5 F = 6 G = 7 H = 8 I = 9 J = 10 K = 11 L = 12 M = 13 N = 14 O = 15 P = 16 Q = 17 R = 18 S = 19 T = 20 U = 21 V = 22 W = 23 X = 24 Y = 25 Z = 26 KNOWLEDGE 96
  • 15.
    Activity: Sub Me In! A= 1 B = 2 C = 3 D = 4 E = 5 F = 6 G = 7 H = 8 I = 9 J = 10 K = 11 L = 12 M = 13 N = 14 O = 15 P = 16 Q = 17 R = 18 S = 19 T = 20 U = 21 V = 22 W = 23 X = 24 Y = 25 Z = 26 HARDWORK 98
  • 16.
    Activity: Sub Me In! A= 1 B = 2 C = 3 D = 4 E = 5 F = 6 G = 7 H = 8 I = 9 J = 10 K = 11 L = 12 M = 13 N = 14 O = 15 P = 16 Q = 17 R = 18 S = 19 T = 20 U = 21 V = 22 W = 23 X = 24 Y = 25 Z = 26 ATTITUDE 100
  • 17.
    VALUES Integration What Equals100%? HARDWORK = 98% KNOWLEDGE = 96% ATTITUDE = 100% LOVE OF GOD = 12+15+22+5+15+6+7+15+4 = 101% While Hard work and Knowledge will get you close, and Attitude will get you there, it's the Love of God that will put you over the top!
  • 18.
    Analysis: 1. What didwe do in our activity? 2. How did we find the value of the given words? When a number is substituted or replaced for the variable in each algebraic expression, the expression takes a numerical value. And finding the value is what we call “Evaluating the Algebraic Expression”. Activity: Sub Me In!
  • 19.
    Evaluating Algebraic Expressions -is substituting a certain number for that variable and performs using the order of the arithmetic operations For example: 1. If 𝑥 = 5, what is the value of 3𝑥 − 4? 2. If 𝑦 = −2 what is the value of 5𝑦 + 3? 3. If 𝑎 = 3 and 𝑏 = −6, what is the value of 2𝑎2 𝑏 − 5𝑎𝑏 + 9?
  • 20.
    Evaluating Algebraic Expressions Thereare at least two steps involved in evaluating algebraic expression: 1. Replacing the variable by the given value (substitution); 2. Performing the indicated arithmetic following the order of operations.
  • 21.
    𝒌 + 𝟗 a.𝑘 = 𝟓 𝑘 + 9 Substitute 5 for 𝑘. = 𝟓 + 9 Add. = 14 Example 1: Evaluate the given algebraic expression.
  • 22.
    𝒌 + 𝟗 b.𝑘 = −𝟐 𝑘 + 9 Substitute −2 for 𝑘. = −𝟐 + 9 Add. = 7 Example 1: Evaluate the given algebraic expression.
  • 23.
    𝟑𝒂 + 𝒃 𝑎= 𝟓 𝑏 = 𝟒 3𝑎 + 𝑏 Substitute 5 for 𝑎 and 4 for 𝑏. = 3(𝟓) + 𝟒 Simplify. = 15 + 4 = 19 Example 2: Evaluate the given algebraic expression.
  • 24.
    𝟓𝒙𝟐 + 𝟏 𝑥 =3 5𝑥2 + 1 = 5(3)2 + 1 = 5 9 + 1 = 45 + 1 = 46 Example 3: Evaluate the given algebraic expression.
  • 25.
    𝟐𝒙𝟐 𝒚 𝒙 − 𝒚 𝑥= 4 ; 𝑦 = 1 2𝑥2𝑦 𝑥−𝑦 = 2 4 2(1) 4−1 = 2(16)(1) 4−1 = 32 3 Example 4: Evaluate the given algebraic expression.
  • 26.
    REAL-LIFE MATHEMATICS DIRECTION: Usethe replacement values provided to determine the cost of each scenario. Cactus and Succulent No. of Cactus (c) and succulent (s) 50c+30s Total 3 cacti and 2 succulents 4 cacti and 5 succulents 2 cacti and 6 succulents Is Php300 enough to pay for 2 cacti and 7 succulents? Yes / No
  • 27.
    REAL-LIFE MATHEMATICS DIRECTION: Usethe replacement values provided to determine the cost of each scenario. Movies No. of tickets (t) and popcorn (p) 200t + 100p Total 5 tickets and 3 containers of popcorn 4 tickets and 4 containers of popcorn Is Php1,000 enough to pay for 4 tickets and 2 containers of popcorn? Yes / No
  • 28.
    NOTES ALGEBRAIC EXPRESSION An algebraicexpression may contain _______________ , _______________ , and one or more _______________ . Examples: 2𝑥 + 7 −𝑥𝑦 + 5𝑧 5𝑚2 − 3𝑚 + 1 constants operations variables
  • 29.
    NOTES CONSTANT A constant isa _______________ . Its value is always the _______________ . VARIABLE A variable is a _______________ that stands for a _______________ . number same letter number
  • 30.
    NOTES EVALUATING ALGEBRAIC EXPRESSION is___________________ a certain number for that _________________ and performs using the order of the arithmetic ________________. substituting variable operations
  • 31.