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Combining like terms

Combining like terms

"Combining like terms" is a process in algebra used to simplify expressions. It involves adding or subtracting terms that have the same variable raised to the same power. For example, in the expression 3x+5x2y+4y3x + 5x - 2y + 4y, you can combine 3x3x and 5x5x to get 8x8x, and combine 2y-2y and 4y4y to get 2y2y. The simplified expression would be 8x+2y8x + 2y. This technique helps to make equations clearer and easier to work with.

Part 1: Intro to combining like terms

Adding like terms is a fundamental concept in algebra. Coefficients are the numbers in front of variables, and they can be added when the variables are the same. For example, 2x + 3x equals 5x. When dealing with different variables, such as x and y, add them separately, resulting in expressions like 5x + 9y.

Here are the key points to learn when studying "Intro to Combining Like Terms":

  1. Definition of Like Terms: Like terms are terms that have the same variable(s) raised to the same power. For example, 3x3x and 5x5x are like terms, while 2x22x^2 and 3x3x are not.

  2. Identifying Like Terms: Look for terms that have identical variable parts. Coefficients (the numbers in front of the variables) can be different.

  3. Combining Like Terms: To combine like terms, add or subtract their coefficients while keeping the variable part the same. For example, 4x+3x=7x4x + 3x = 7x.

  4. Simplifying Expressions: Combining like terms helps to simplify algebraic expressions, making them easier to work with.

  5. Examples and Practice: Work through several examples, identifying and combining like terms in different expressions, such as polynomials.

  6. Order of Operations: Remember that combining like terms is part of the simplification process, which often follows the order of operations when solving equations.

  7. Multi-variable Expressions: In expressions with multiple variables, only combine terms that are exactly the same. For example, 2xy+3xy2xy + 3xy can be combined, but 2xy+3x2xy + 3x cannot.

  8. Application: Practice combining like terms in various mathematical problems to gain proficiency.

By focusing on these points, you'll build a strong foundation for understanding and working with combining like terms in algebra.

Part 2: Combining like terms with negative coefficients & distribution

We've learned about order of operations and combining like terms. Let's layer the distributive property on top of this.

Here are the key points to focus on when studying "Combining Like Terms with Negative Coefficients & Distribution":

  1. Definition of Like Terms: Understand that like terms are terms that have the same variable raised to the same power. For instance, 2x2x and 3x-3x are like terms.

  2. Combining Like Terms:

    • When combining like terms, add or subtract the coefficients while keeping the variable part unchanged.
    • Be mindful of negative coefficients; for example, 2x3x=1x2x - 3x = -1x.
  3. Distributive Property: Recognize that the distributive property states a(b+c)=ab+aca(b + c) = ab + ac. This applies to both addition and subtraction:

    • Example: 2(x+3)=2x+62(x + 3) = 2x + 6 and 3(x4)=3x123(x - 4) = 3x - 12.
  4. Applying Distribution with Negatives: When distributing negative coefficients, remember to distribute the negative sign as well:

    • Example: 2(x+3)=2x6-2(x + 3) = -2x - 6.
  5. Simplification Process: After applying distribution, always combine like terms to simplify the expression further.

  6. Practice Problems: Work through various examples with both combining like terms and using distribution with negative coefficients to solidify understanding.

Focus on these points to build a strong foundation in working with expressions that involve both combining like terms and using distribution effectively.

Part 3: Combining like terms with distribution

Learn to expand and simplify an expression like 3(5x+6) + (7x+2)*4.

When studying "Combining Like Terms with Distribution," focus on these key points:

  1. Understanding Like Terms: Like terms are terms that have the same variable raised to the same power. They can be combined by adding or subtracting their coefficients.

  2. Distribution: The distributive property allows you to multiply a single term by each term inside a set of parentheses. The formula is a(b+c)=ab+aca(b + c) = ab + ac.

  3. Applying Distribution: When you distribute, ensure to multiply each term correctly and pay attention to signs (positive or negative).

  4. Combining After Distribution: Once you've applied the distributive property, combine like terms by adding or subtracting their coefficients.

  5. Final Simplification: The result should be in its simplest form, featuring no like terms left to combine.

These concepts are crucial for simplifying expressions effectively in algebra.

Part 4: Combining like terms with negative coefficients

This example of combining like terms in an expression gets a little hairy. Pay attention.

When studying "Combining like terms with negative coefficients," focus on these key points:

  1. Definition of Like Terms: Like terms are terms that have the same variable raised to the same exponent. For example, 3x3x and 2x-2x are like terms.

  2. Identifying Coefficients: The coefficient is the numerical factor in front of a variable. Understand how to identify positive and negative coefficients.

  3. Combining Terms: To combine like terms, add or subtract their coefficients:

    • For example: 3x+(2x)=(32)x=1x3x + (-2x) = (3 - 2)x = 1x.
  4. Handling Negative Coefficients: Be careful with subtraction involving negative coefficients:

    • For example: 5y3y5y - 3y becomes 5y+(3y)=(53)y=2y5y + (-3y) = (5 - 3)y = 2y.
  5. Simplification: Always simplify your final answer to its lowest terms, ensuring it accurately represents the expression.

  6. Examples Practice: Work through various examples to reinforce your understanding, focusing on expressions with different combinations of positive and negative coefficients.

By mastering these points, you'll be able to effectively combine like terms, regardless of their coefficients.

Part 5: Combining like terms with rational coefficients

Learn how to rewrite algebraic expressions by combining like terms. The expressions in this video have decimal and fraction coefficients.

When studying "Combining Like Terms with Rational Coefficients," focus on the following key points:

  1. Definition of Like Terms:

    • Like terms are terms that have the same variable raised to the same power, though their coefficients (numbers in front) can be different.
  2. Identifying Like Terms:

    • Look for terms with identical variable parts (e.g., 3x3x and 5x5x are like terms, while 3x3x and 2y2y are not).
  3. Rational Coefficients:

    • Understand that coefficients can be rational numbers (i.e., fractions or whole numbers).
  4. Combining Process:

    • To combine like terms, add or subtract their coefficients while keeping the variable part the same (e.g., 3x+5x=8x3x + 5x = 8x).
  5. Simplification:

    • After combining, simplify the expression as much as possible to arrive at the most compact form.
  6. Maintaining Structure:

    • Pay attention to the signs of the coefficients when combining terms, especially when dealing with negative numbers.
  7. Application:

    • Practice combining like terms in various algebraic expressions to strengthen understanding.

By mastering these points, you'll be well-equipped to effectively combine like terms with rational coefficients.