Introduction to Algebraic Expressions
Do you want to learn about algebraic expressions in detail? If you do, you’ve come to the right article.
Algebraic expressions come from the declaration of algebraic terms. In mathematics, an expression means the phrase form of different mathematical terms.
In this article, we will begin by defining an algebraic expression and explaining its types in detail. We will also provide solved examples so that every student can cover the basics of algebraic expressions.
This concept proceeds from the school level to the real world. It is useful in budgeting, cooking, calculating travel time, and in many other fields. Let’s start our journey into algebraic expressions.
Definition and Meaning of Algebraic Expression:
The word Algebraic is derived from algebra, and expression comes from express. An algebraic expression is a combination of different algebraic terms (variables, constants, coefficients, and operations).
For example
2x+ 5 – 9
3y + 7 – 6
7y × 5
Do you notice that there is no equal sign in these examples? The main reason is that algebraic equations have an equal sign, not an algebraic expression.
Learn more in our detailed guide on algebraic equations.
Key Terms in Algebraic Expressions:
In the above section, we’ve discussed some algebraic terms. Here, we will talk through the basic components of algebraic expressions.
1. Variables:
Variables originate from the term “vary,” which means keep changing. The letter whose value is not fixed is called a variable in an algebraic expression.
For example:
2x + 5 – 9
3y + 7 – 6
In these examples, x and y are variables.
2. Constants:
Those numbers are constants (unchangeable, fixed).
For example
- 2x + 5 – 3
- 3y + 7 – 6
Here, -3, 5, -6, and 7 are constants.
3. Coefficients:
Constants that multiply a variable are called coefficients.
For example,
9x + 8 – 9
3y + 4
In this example, 9 and 3 are coefficients.
Components of Algebraic Expressions in the Form of a Table:
| Expressions | Variables | Constants | Coefficients |
| 4x + 7 – 8 | x | 7, -8 | 4 |
| 2y – 7 | y | -7 | 2 |
| 3z + 8 – 1 | z | 8, -1 | 3 |
| 2a + b – 3c | a, b, c | 0 | 2, 1, -3 |
| x/2 | x | 0 | 1/2 |
If there is nothing with the variable, then the coefficient is 1.
Activity of Finding Key Terms through Examples
Here is a self-assessment for you to find the key terms of algebraic expressions from the examples given below, so that your concept becomes clear.
- 2x + 7 – 4
- 5x – 30
- 7x
- 5+ 7 – 3
- x/2 + x – 9
Types of Algebraic Expression with Examples:
The following are the types of algebraic expressions for beginners so that students can understand them easily.
- Monomial Expression:
The word mono means one. An expression in which only one term is used is called a monomial expression.
For example:
2x, 5y,
- Binomial Expression:
Here, bi means two. So, the expressions that contain two terms are called binomial expressions.
For example:
2x + 6
4y – 7
- Trinomial Expressions:
An expression having three terms is known as a trinomial expression.
For example:
4x + 3y – 7
2x2 + 3x + 1
- Polynomial Expression:
“An expression with one or more terms and non-negative integer powers of variables is called a polynomial expression.”
For example:
2x2+ 4x +1
2x3 + 3x2 – 5x +1
For further reading, see the explanation of algebraic expressions on BYJU’S.
Activity for Types of Algebraic Expressions through Examples:
Hint:
If you keep in mind the above section, then you can detect the exact type by counting the terms easily.
- 3a – 5b
- 2x + 5y – 7
- -2a
- x3 – 4x + 6
- -2a2
Algebraic Expressions Solved Examples:
Here you will find algebraic expressions questions, which you will have to solve step by step to understand this topic perfectly. These questions are suitable for Algebraic expressions for classes 6, 7, and 8. While solving each question, BODMAS should be kept in mind.
- Find the value of x+7 if x=5
Solve:
x + 7 = 5 +7 =12
- Evaluate 3y if y=4
Solve:
3y = 3(4) = 12
- Find the value of 5a−2 if a = 6
Solve:
5a – 2 = 5(6) – 2 = 30 – 2 = 28
- Evaluate 4m+3 if m=2
Solve:
4m + 3 = 4(2) + 3 = 8 + 3 = 11 - Find the value of 12−p if p=9
Solve:
12 – p = 12 – 9 = 3 - Evaluate x2 if x=5
Solve:
x2 = 52 = 25 - Find the value of x2+3x if x=2
Solve:
x2+ 3x = 22 + 3(2) = 4 + 6 = 10 - Evaluate 2a2−a if a=3
Solve:
2a2 – a = 2(3)2 – 3 = 18 – 3 = 15
- Find the value of 3m+n if m=4, n=5
Solve:
3m + n = 3(4) + 5 = 12 + 5 = 17 - Evaluate x+y+6 if x=3, y=1
Solve:
x + y + 6 = 3 + 1 + 6 = 10
Practice Problems of Algebraic Expressions:
- Find the value of 2x+5 if x=4
- Evaluate 7y−3 if y=2
- Find the value of a+4 if a=3
- Evaluate 3m−2n if m=5, n=1
- Find the value of x2+y if x=2, y=6
FAQ’s:
- What are common algebraic mistakes?
The common mistake that confuses every student while solving problems is the addition and substitution rules.
- What is the specialty in algebraic expressions?
The strong point is that in this case, there is no equal sign.
- What is the rule for simplifying algebraic expressions?
The BODMAS rule occurs during problem-solving.
- How many variables are in an algebraic expression?
It is necessary to have a minimum number of variables in an algebraic expression.
- What are the basic components of algebraic expressions?
The basic components are variables, constants, coefficients, and operators.
Conclusion:
This article analyzes algebraic expressions in detail. After covering their components, their types, and solved examples, hope you have understood this topic.