Topic: Function and Relation

1. Lesson Plan
Relation and Function
Objectives
With-in the period, students are expected to:
a. Define the relation and function;
b. Interpret a relation and a function;
c. Associate relation and function in real life situation.
Subject Matter
Topic: Relation and Function
Reference: Grade 8 mathematics book, CK-12 Flex Book App.
Materials: Visual Aids, Blackboard, LCD Projector, Chalk
Competency:
- Illustrates relation and function

2. A. Daily Routine
1. Prayer
Good afternoon class. Please all rise
and let us pray.
2. Cleaning
Okay class, before you sit down, please
pick up the pieces of paper and kindly
throw it into the trash can.
3. Greeting
Good afternoon once again class. How
are you today?
4. Checking of Attendance
Is anyone absent for today’s class?
Very good!
B. Priming
1. Recall
Since we are already done about linear
inequalities, let us proceed now to our
new lesson.
2.Motivation
Okay class, who among of you wants
to have a prize?
So all of you wants to receive a prize.
Since you have already your group, we
are going to have a game called paint-
me-a-picture.
Do you know how to play that game
class?
Very good! But our game has a twist.
Group 1 and group will be one team
and group 3 and group 4 will also be
one team. The main twist here is that
the other group will be the cause of the
scene and the other group will do the
effect of the scene. When I say freeze
everyone will stop moving. Is that
clear?
First, paint-me-a-picture of destroyed
environment.
Okay class, freeze!
Second, paint-me-a-picture of clean
environment.
A. Daily Routine
1. Prayer
(The students will stand and pray.)
2. Cleaning
(The students will pick up pieces of
paper and throw it into the trash can.)
3. Greeting
Good afternoon teacher! (Students
will have different responses)
4. Checking of Attendance
None teacher.
B. Priming
(The students will raise their hands.)
(Students are Excited)
Yes Teacher!
Yes teacher!
(The students will assemble
themselves.)
(The students will assemble
themselves.)

3. Okay class, freeze!
Since all of you did a great picture,
everyone will be receiving an
additional 10 points to your quizzes.
C. Activity
Okay class. I have prepared for you an
activity. This will be an individual
activity.
In this activity, I want you to analyze
during our game if what mathematical
concept/s could you drawn from the
game. I’ll give you 5 minutes to do
that. You may start your activity now
and write it in a 1 2⁄ crosswise paper.
D. Analysis
1. What is a relation?
2. How things relate to each other?
3. Does the other set have function to
the other in terms of their relation?
4. What is a function?
Okay class. Time is up!
So any volunteer to share his/her work
here in front?
Very well said! Does everyone have
the same answers with classmates who
presented their work?
Very good! Does anyone could relate
this mathematical concept in real life
situation?
Very well said class!
E. Abstraction
Now, does anyone know what will be
our topic today?
Very good! Let us give him 3 claps.
Let us now proceed to the discussion.
Since you determined that there is a
relation in your activity, what is a
relation?
Very good! Then what is an ordered
pair?
(Everyone is happy.)
C. Activity
(The students will do the activity.)
D. Analysis
(Student will stop from writing.)
(Someone will present his/her work.)
Yes teacher!
(Students will raise their hands; having
different answers)
E. Abstraction
It is about relation and function teacher.
(3 claps)
A relation is any set of one or more
ordered pairs.
A set of two ordered real numbers
called coordinates.

4. Very good! Can you consider this a
relation?
X Y
Very good! What is there relation to
each other?
Very good! Class, please always
remember that set X is our domain and
set Y is our range. Is that clear?
In this figure, is this also a relation?
Very good! Anyone knows what is the
meaning of a function?
Very good always remember class that
for every value X or our domain has
only one value of Y or our range. Is
that clear?
Very good. Let us go back to this
diagram. Is this relation is a function?
Very good! But why?
Very good! Is this next diagram a
function?
Yes teacher.
In the set X they are the capital of the
country in set Y.
Yes teacher.
Yes teacher.
A relation in which elements of the
domain is paired with exactly one
element of the range.
Yes tteacher.
Yes teacher.
As the definition of a function, there is
only one correspond for every number
in Set X or domain.
Yes teacher.
Manila
Jakarta
Bangkok
Philippines
Indonesia
Thailand
1
2
3
4
5
6
3
4
5
7
8

5. Very good. What is the relation
between these elements?
Very good. Then what relation can’t be
considering as a function?
Very good. Then what relation could
be considering as a function?
Very good. Another reminder to
everyone, always remember that a
function can always be a relation but a
relation cannot be always a function.
Generalization
Are there any questions regarding to
our lesson for today? Let us have a
recap.
What is a function?
How could you determine if it is a
relation considered as a function?
How could you determine if s a relation
but not consider as a function?
Very good. You all did understand our
lesson. Let us have our exercise.
1. Give 2 example each relation that
can be consider as function.
2. Give 2 example each relation that
cannot be consider as a function.
Time is up! Please pass all your papers.
F. Application
I will not give a quiz for today for I
know everyone understand lesson.
G. Assignment
For your assignment, please read in
advance about relation and function
using ordered pairs, graphs and
equations.
A one-to-one relation teacher.
Only one-to-many relation teacher.
The one-to-one and many-to-one
relation teacher.
None teacher.
A relation in which elements of the
domain is paired with exactly one
element of the range.
If it is one-to-one or many-to-one
relation teacher.
If it is one-to-many relation teacher.
(Students answers the exercises)
F. Application
G. Assignment