Let's break down the key terms one by one, providing definitions, meanings, pictures, and examples with problems.
1. Expression
Definition:
An expression is a combination of numbers, variables, and mathematical operations (like addition, subtraction, multiplication, and division) that represents a value.
Meaning:
An expression does not have an equals sign. It can be simplified or evaluated, but it cannot be solved as an equation can.
Picture:
An example of an expression is \(3x + 5\).
Example Problem:
Evaluate the expression \(3x + 5\) for \(x = 2\).
Steps:
-
Substitute \(x\) with \(2\):
\(3(2) + 5\) -
Perform the multiplication:
\(6 + 5\) -
Add:
\(11\)
Final answer: \(11\).
2. Terms
Definition:
Terms are the individual components of an expression that are separated by addition or subtraction operators.
Meaning:
Each term can be a constant (number), a variable, or a combination of both multiplied together.
Picture:
In the expression \(4x^2 + 3x - 7\), the terms are \(4x^2\), \(3x\), and \(-7\).
Example Problem:
Identify the terms in the expression \(2x + 5y - 3z + 8\).
Steps:
- The terms are \(2x\), \(5y\), \(-3z\), and \(8\).
Final answer: Terms are \(2x\), \(5y\), \(-3z\), \(8\).
3. Factors
Definition:
Factors are the quantities we multiply together to get another number or expression.
Meaning:
In algebra, factors can be numbers, variables, or both.
Picture:
In the expression \(6x\), \(6\) and \(x\) are factors.
Example Problem:
Factor the expression \(10xy + 15x\).
Steps:
- Identify the common factor of the terms: The GCF (Greatest Common Factor) is \(5x\).
- Factor \(5x\) out of each term:
\(5x(2y + 3)\)
Final answer: \(5x(2y + 3)\).
4. Coefficients
Definition:
Coefficients are the numerical factors that multiply a variable in a term.
Meaning:
They indicate how many times to multiply the variable. If a term does not have an explicit coefficient, it is assumed to be \(1\).
Picture:
In the term \(7x\), \(7\) is the coefficient.
Example Problem:
Identify the coefficients in the expression \(4x^2 - 3x + 7\).
Steps:
- For the first term \(4x^2\): Coefficient is \(4\).
- For the second term \(-3x\): Coefficient is \(-3\).
- For the constant term \(+7\): The coefficient of a constant is not explicitly stated, but we refer to it as \(7\) (it does not have a variable).
Final answer: Coefficients are \(4\), \(-3\), and \(7\).
Summary Table
| Term | Definition | |---------------|------------------------------------------------------------------------| | Expression | A combination of numbers, variables, and operations representing a value. | | Terms | Individual parts of an expression separated by '+' or '-' operators. | | Factors | Numbers or variables that multiply together to produce another number. | | Coefficients | Numerical factors that multiply the variables in terms. |
These definitions and examples should provide a solid understanding of the key terms related to expressions in algebra! If you have any additional questions, feel free to ask!