Learn Class 7 Math - Algebraic Expressions

The term algebraic expression refers to the expressions available in the form of variables. These are the complete set of operations, including addition, multiplication, division, and subtraction. Example 2x + 5 is known as an algebraic expression.

Variable

  • The term variable consists of the symbols not present in the fixed values.
  • Example: 2x + 5, in this x is known as the variable.

Constant

  • The term constant refers to the symbols present with the fixed values.
  • We can say that all the given numbers are constants.
  • Example: 2, 3, 6, etc.

Coefficients

  • The term coefficients refer to the number present with the given variable.
  • Example: 2x + 5, the variable is x, and its coefficient is 2.

Set of formulas

The algebraic set of expressions includes a different set of formulas. These formulas are discussed here below:

  1. (a + b) ^2 = a^2 + b^2 + 2ab.
  2. (a - b) ^2 = a^2 + b^2 - 2ab.
  3. (a + b) (a - b) = a^2 - b^2.
  4. (x + a) (x + b) = x^2 + x (a + b) + ab.

Different expressions

The algebraic expressions are present in different types. Such as monomial, binomial, polynomial, trinomial, multinomial.

Problem

Can we explain that 12 y / x? Evaluate the answer.

Solution

In this expression, we can see that it does not consist of the non-zero term. It also consists of the denominator that comes in variables. We can say that 12 y / x is not present in the form of a monomial.

Algebraic Expressions Sample Questions for Class 7

Question 1

3xy + 2y − xy + x – y + 2x = ?
A. 4xy + 3x + y
B. 2xy + 3x + y
C. xy + x + 3y
D. xy + x + y

Question 2

Number of sides on either side of equation in simple equation is
A. Three
B. Two
C. 0
D. None

Question 3

‘6 less than ten times a’ is written as
A. 6 – 10a
B. 10a – 6
C. 10ac
D. 6 < 10 × a – 6

Question 4

Deepak made a total of Rs. 130 by selling 5 magazines and 6 coupon books. He sold each coupon book for Rs. 12.50. Which equation can you use to find the cost, c, of each magazine?
A. 5 + c + Rs. 12.50 × 6 = 130
B. 6c + Rs. 12.50 × 5 = 130
C. 5c + Rs. 12.50 × 6 = 130
D. c + Rs. 12.50 × 6 = 130 – 5c

Question 5

Write as an algebraic expression. Number of hours in d weeks.
A. 168 + d
B. 22 ÷ n = 9
C.
D. 168d