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104 LearnersLast updated on October 22, 2025

The term ‘x squared’ refers to the expression x2, where x is multiplied by itself. In this article, we will learn more about squaring and its applications in real life.
In algebra, when x is multiplied by itself, it is written as x2. Here, x is the base and 2 is its exponent. In other words, for any variable x, x2 is an algebraic notation that refers to a number being multiplied by itself i.e., x . x=x2.
The value of x2 can be found by multiplying the value of x with itself.
Let us take a few examples to see how:
Example 1. If x = 3
x2 = 3 × 3 = 9
Example 2: If x = - 4
x2 = (- 4) × (- 4) = 16
Example 3: If x = 0
x2 = 0 × 0 = 0
Example 4. If x = 1.5
x2 = 1.5 × 1.5 = 2.25
Example 5. If x = 2/5
x2 = (2/5)×(2/5)=4/5
Perfect squares are products of an integer multiplied by itself. So, if x is an integer, then x2 is a perfect square.
Given below is a chart of the first 50 perfect squares for your reference.
The square root of a variable x is the number that, upon multiplying by itself, gives x as the product. It is written as √x. The square root of x2 is |x| because x × x=(-x) × (-x)=x2
So, √x2 = x or x
For example, if x = - 7
√x2 =√(-7)2 =√49 =7=7 or 7
x squared and 2x do not mean the same thing. In x2, x is the base and 2 is the exponent. In 2x, 2 is the coefficient of x, indicating that x is multiplied by 2.
For example, If x = 11,
then x2 = x × x = 11 × 11 = 121, and
2x = 2 × x = 2 × 11 = 22
The sum of squares can be found using the formula,
a2+b2=(a+b)2-2ab
For instance, let’s take a = 3 and b = 4,
Substituting the values in the formula provided above, we get,
32 + 42 = (3 + 4)2 - 2(3)(4)
= 49 - 24
= 25
To find the difference of squares, we use the formula,
a2-b2=(a+b)(a-b)
Let’s assume that a is 6 and b is 2
Substituting the values, we get,
62 - 22 = (6 + 2)(6 - 2)
= 8 × 4
= 32
The formula for the difference of two perfect squares helps simplify complex algebraic expressions. It is useful while writing algebraic expressions as factors.
Let’s say there are two numbers x and y. To calculate the difference of their squares, we use the formula,
x2 - y2 = (x + y)(x - y)
Let us take x = 2 and y = 7
22 - 72 = (2 + 7)(2 - 7)
= 9 × (-5)
= -45
Completing the square refers to expressing a quadratic expression ax2 + bx + c as a(x + d)2 + e.
Where
a is the coefficient of x2 from the original expression.
d comes from b/2a, so (x + d)2 is the part that is being completed.
e is the adjustment constant added to balance the expression after completing the square. It is calculated as e = c - a(b/2a)2 =c-b2/4a.
For example, let’s complete the square for 2x2 + 8x + 5
Step 1: Factor out the coefficient of x2
= 2(x2 + 4x) + 5
Step 2: Complete squaring inside parentheses
42= 2, 22 = 4
Now add and subtract 4 inside the parentheses
= 2(x2 + 4x + 4 - 4) + 5
= 2((x + 2)2 - 4) + 5
= 2(x + 2)2 - 8 + 5
= 2(x + 2)2 - 3
The completed square form of 2x2 + 8x + 5 is 2(x + 2)2 - 3
Here, a = 2, d = 2 and e = - 3.
Students might make small mistakes that may go unnoticed while finding solutions related to x2. Although trivial, these mistakes can lead to incorrect answers. Given below is a list of a few such errors and tips to avoid them.
X squared as a mathematical concept has many real-life applications. From architecture to astronomy, x squared is used in many fields, some of which are discussed here:
If x = 5, what is the value of x2?
25
x2 = 52 = 5 × 5 = 25
If x2 = 100, what is the value of x?
x = 10
If x2 = 100, then taking the square roots of both sides we get,
√x2 = √100 = 10.
The answer is both positive and negative because both (10)2 and (-10)2 will give us the same solution, which is 100. So, both values are valid solutions when solving the equation x2 = 100.
Simplify (3x)2, x = 2.
36
(3x)2 = 9x2
9x2 = 9(2)2 = 9 × 4 = 36
A square has a side length x = 7cm. What is its area?
49cm2
Area of square = x2,
Here, x = 7, so Area of square = 72 = 49cm2
An object is moving at a speed x = 5 m/s, and its kinetic energy is proportional to the square of its speed. Find the value of kinetic energy.
25
Kinetic energy = x2
X = 5, so x2 = 52 = 25
Jaskaran Singh Saluja is a math wizard with nearly three years of experience as a math teacher. His expertise is in algebra, so he can make algebra classes interesting by turning tricky equations into simple puzzles.
: He loves to play the quiz with kids through algebra to make kids love it.






