Expression is an algebraic or mathematical statement involves numbers,one or more variables and the operation symbols like
+,-, x ,÷.

Look at the flash cards below.They show the mathematical equations for different statements.

Example using addition:

A boy is purchasing 2 pencils and 5 erasers with cost of $ 30. Construct the equation for this case.

Now we are going to take the variable x as cost of 1 pencil and y as the cost of 1 eraser. So the required equation is 2x + 5y = 30

Example using subtraction:

In a two digit number the difference of the digits of a number is 5. Construct the a equation for this case.

Now we are going to take the two digit number be "xy". Here the difference of two digit number is 5. So we can form the equations as x - y = 5.

Example using multiplication:

Example using division:

Here are the some examples of writing statement.

Examples :

Rewrite the following as a algebraic equation.

1. The product of x and y is "xy"

2. The sum of m and n is " m + n "

3. Five less than x is "x-5"

4. The sum of x,y and 5 times z is "x + y + 5z"

5. The difference between a and the product of b and c is " a - bc " Definition of variable

A letter used in a mathematical statement to represent a number is called a variable.

In these statements "x" is the variable let us consider the examples "x + 5",12x, x³/2.

An algebraic or mathematical-equation involves numbers, one or more variables and the operations symbols like + , -, x or ÷

The + and - signs in an algebraic statements separate it into terms.

Here are the two practice worksheets on the topic. Students need to practice this kind of question to form a expression from the statement. This is the most important part to students who are struggling to face a word problem.