# Equation (+ what is the unknown) - Examples, Exercises and Solutions

But before explaining what unknowns are, it is important that we review the concept of what a mathematical equation is:

• An equation is an algebraic expression that includes numbers (fixed values), and also letters with unknown value (unknowns). Our goal is to arrive at a solution to the equation, that is, to find the missing value (the unknown), so that both sides of the equation are equal.

## What is an unknown?

In general, we express the unknowns with the letters $X$, $Y$ or Greek letters such as alpha and beta. Most of the time we will be asked to find the unknown value to be determined by solving an equation.

## examples with solutions for equation (+ what is the unknown)

### Exercise #1

$5x=0$

### Video Solution

$x=0$

### Exercise #2

$5x=1$

What is the value of x?

### Video Solution

$x=\frac{1}{5}$

### Exercise #3

$14x+3=17$

### Video Solution

$x=1$

### Exercise #4

$2x+7-5x-12=-8x+3$

### Video Solution

$x=\frac{8}{5}$