X Definition

In algebra, “x” is used to show any term that is still unknown. It means the value that is unknown in the given expression or equation is shown by “x” generally in Algebra.

It is also termed a variable in the given expression that can be changed according to the statement of the expression. It is not a hard and fast rule to show an unknown value by “x” but it can also be shown by “y” and “z”.

For Example

In this equation,

x + 8 = 12

"x" is used to display an unknown value

The opposite of a variable in an equation is “Constant”. You can read about “Constant” in detail here.

How to find “x” from an equation?

An unknown variable can be found by rearranging the equation, addition, subtraction, multiplication, and division. It depends on your question statement which operation you should go with to find the value of “x”.

Here are a few examples following all these basic Mathematical operations to find the value of an unknown variable.

Example 1:

Find “x” from the following equation

x - 7 = 21

Solution:

To solve this equation, we have to rearrange the equation first and then add the numbers.

x = 7 + 21
x = 28

Example 2:

Find “x” from the following equation

x + 8 = 32

Solution:

x = 32 - 8
x = 24

Example 3:

Find “x” from the following equation

2x = 62

Solution:

To solve this equation, we have to rearrange the equation first and then subtract the terms.

\[m = \frac{{{62} {}}}{{{2} {}}}\]

\[x = {{{31} }}{{ }}\]

Example 4:

Find the value of “x” from the following equation: \[\frac{{{x}}}{{{13}}}=7\]

Solution:

To solve this equation, we have to multiply the denominator of x on the right-hand side of the equation.

x = 13(7) 
x = 91