Applications of Algebraic Expressions

We will discuss about the applications of algebraic expressions in everyday life. 

The most important use of algebraic expression is to solve a word problem by translating the word statement to that statement in the symbols of algebra. Writing an algebraic expression which represents a particular situation is called an algebraic representation.

Algebraic representations of some practical situations are as follows:

A mathematical sentence with an equality sign is called statement of equality.

For example: x + 5 = 9

Statements of equality involving one or more variables is called an equation.

or

An equation is an equality between two algebraic expressions/statements.

The sign of equality in an equation divides it into two sides, namely left hand side (L.H.S) and right hand side (R.H.S). L.H.S and R.H.S of an equation are like the two scales of a balance.

For example: 

Working Rules for Make an Algebraic Expression:

Step I: Take any variables, say x.

Step II: Perform any of the four operations i.e., add, subtract, divide or multiply on that variable x to make an algebraic expression.

Step III: Make the algebraic expression a statement of equality.

Step IV: The result will involve a variable with a statement of equality which is called an equation.

Solved Examples on Applications of Algebraic Expressions:

1. Write an algebraic expression 6 less than one-fourth of'x'.

Solution:

One-fourth of x = $\frac{1}{4}$ x = $\frac{x}{4}$

6 less than one-fourth x = $\frac{x}{4}$ - 6 which is the required equation.

2. Write an equation for each of the following statements:

(i) The difference between x and the sum of 2 and 3 is 11.

(ii) The sum of $\frac{4}{5}$th of x and five times x is 140.

Solution:

(i) The sum of 2 and 3 = 2 + 3.

Now, the difference between x and the sum of 2 and 3 is 11, is given by

x - (2 + 3) = 11

or, x - 5 = 11 which is the required equation.

(ii) $\frac{4}{5}$ th of x = $\frac{4x}{5}$ and five times x = 5x

Now, the he sum of $\frac{4}{5}$th of x and five times x is 140, , is given by

$\frac{4x}{5}$ + 5x = 140, which is the required equation

Algebra Page

6th Grade Page

From Applications of Algebraic Expressions to HOME PAGE