Adding and Subtracting Polynomials

Mathematics 7

Prepared by: Teacher Maria

Review Time!

- Monomial Ex. 2x, 5x, 2y, 6y
- Binomial Ex. 3x+5, 6x+3y
- Trinomial Ex. 3s-5t+7, 2x+9y-8
- Polynomial Ex. 3x+4y-5z+6w

Different types of Polynomials

Motivation

Instruction:
​The class will be divided into four (4) groups and will play a short quiz on Quizizz. The code for the quiz is sent on the group chat of the class. The group who will gain the highest score will receive a badge that is equivalent to 10 points.

Multiple Choice

Q1. The variables x and y are the same.

• True

• False

Multiple Choice

Q2. $$9-10$$ is equal to $$19$$ .

• True

• False

Multiple Choice

Q3. The sum of $$2x$$ and $$3x$$ is $$5x$$ .

• True

• False

Multiple Choice

Q4. The difference of $$3x$$ and $$4y$$ is $$3x-4y$$ .

• True

• False

What does it have to do with our lesson?

Addition and Subtraction of Polynomial

Objectives

At the end of the lesson, the learners will be able to:

• add and subtract polynomial expressions;

• demonstrate the steps for adding and subtracting of polynomials using the appropriate mathematical operations; and

• demonstrate the application of addition and subtraction of polynomials in real-life situations through an amazing race activity.

Defining terms

Like Terms

Unlike Terms

Defining terms

Like Terms

• Like Terms are terms whose variables, along with their exponents, are the same.

• For example, 2x, 7x, -2x, etc. are all like variables.

Defining terms

Like Terms

• Like Terms are terms whose variables, along with their exponents, are the same.

• For example, 2x, 7x, -2x, etc. are all like variables.

Unlike Terms

• Unlike Terms are terms whose either variables, exponents, or both variables and exponents are the not the same.

• For example, 2, 7x², -2y², etc. are all unlike variables.

Multiple Choice

Which of the following are like terms?

• x² and 2x

• 3x and 4y
• 5x and 5x²

• 14x and -5x

Multiple Choice

Which of the following are unlike terms?

• x³ and 3x

• 5y and 4y

• y and 10y

• 14x and -5x

How Can We Add Polynomials?

• To add polynomials, simply combine like terms or similar terms.

• To combine similar terms, get the sum of the numerical coefficients and copy the same literal coefficients.

How Can We Add Polynomials?

• To add polynomials, simply combine like terms or similar terms.

• To combine similar terms, get the sum of the numerical coefficients and copy the same literal coefficients.

Rules in adding polynomials

Rule 1: Always take like terms together while performing addition.

Rule 2: Signs of all the polynomials remain the same.

Example:

Example:

Example:

How Can We Subtract Polynomials?

• To subtract a polynomial from another polynomial, change the sign of the subtrahend and proceed to addition.

How Can We Subtract Polynomials?

• To subtract a polynomial from another polynomial, change the sign of the subtrahend and proceed to addition.

subtrahend

minuend

Keep, Change, Change

sign of
minuend

sign of subtrahend

operation to +

How Can We Subtract Polynomials?

• To subtract a polynomial from another polynomial, change the sign of the subtrahend and proceed to addition.

Rules in subtracting polynomials

Rule 1: Always take like terms together while performing subtraction.

Rule 2: Apply the Keep, Change, Change technique.

Example:

Example:

Example:

Example:

Example:

Summary of the lesson

Summary of the lesson

In adding polynomials:

• only add like terms

Summary of the lesson

In adding polynomials:

In subtracting polynomials:

• only add like terms

• only subtract like terms

• apply the Keep - Change - Change method

Do you have any questions and clarification?

Activity 1
Amazing race with a twist

Activity 1
Amazing Race with a Twist

​Direction: With the same groupings, each group has to go through the three (3) stations prepared and each station contains a question that will be answered in 1 minute through the Quizizz app. Each question corresponds to a certain point and the group with the highest score will gain 30 points.

Multiple Choice

Station 1 Question

• A. 5𝑥 − 5

• B. 5𝑥 + 5

• C. 5𝑥 – 11

• D. 5𝑥 + 11

Congratulations to the winning group

Activity 2
Quiz Bowl

Activity 2 - Quiz Bowl

Direction: With the same groupings, each group will be given 20 seconds to answer each question on Quizizz. There will be a total of 10 questions and the group with the highest points will gain 20 points.

What can you say about the activities we did?

What can you say about the activities we did?

You will be answering a 20-item quiz at home on Quizizz using you own accounts individually. The person who will get the 1st place will be given a special prize next meeting.

​Assignment Time!

Questions? Clarifications?

Good bye class!

​Prepared by: Teacher Maria