According to Mathematics experts, an equation (a concept derived from the Latin *aequatio*) constitutes an equality where at least one unknown appears that requires to be revealed by the person who solves the exercise. Members are known as each of the algebraic expressions that allow knowing the data (that is, the values already known) and the unknowns (the values that have not been discovered) linked through various mathematical operations.

It should be noted that the data included in an equation can be numbers, constants, coefficients or variables. The unknowns, on the other hand, are represented by letters that substitute the value that you are trying to find. According to Abbreviationfinder, EQN stands for Equation.

A simple equation is the following:

4 + x = 9

In that equation, 4 and 9 are the data, while x is the unknown. The equation can be solved in the following way:

4 + x = 9

x = 9 – 4

x = 5

The value of the unknown, therefore, is 5.

In the field of Chemistry, on the other hand, equation is understood as the expression that, in a symbolic way, represents a chemical reaction. With it, then, it is possible to indicate the relative amounts of both the reactants and the products.

In the field of astrology, likewise, an equation is characterized by being the difference that emerges from the comparison of the mean movement with the true or apparent displacement of a star.

Finally, it should be noted that the term equation is used in everyday language to refer to formulas or calculations that involve different variables. For example: *“If I buy a new car for $30,000 and I don’t get promoted at work, the equation is not going to work”*, *“The equation, in my opinion, is simple: you should quit your current position, invest the money that you have saved and open your own company”*.

E = mc2

Undoubtedly, the most famous and misunderstood equation is that of Albert Einstein’s Theory of Relativity, which represents a huge step for science in the 20th century. Although he was not the one to develop the concept of relativity in the first place, his work attempted to show that the speed of light is constant if it is in a vacuum.

Basically, physicists divide the Theory of Relativity into two parts or well-differentiated versions: the Special, which studies the possible relativity of inertia and motion, as well as the repercussions of what Einstein conjectured, and the General, which is focuses on the acceleration of particles and radically questions the theory proposed by Newton, since it predicts different results for bodies that move at high speeds, have a large volume, or both.

Although the latter can faithfully reproduce all the predictions verified in the Newtonian theory, it takes the understanding of some of its basic principles to new horizons. For example, Newton had developed that gravity worked in empty space, although he did not delve into reasons why the distance and mass of a given object could be transmitted through it. In this case, Einstein’s vision helps to resolve the paradox, showing that the movement persists in a straight line, although it is observed by us as acceleration, since the space-time relationship has a curved nature.

In recent times, both parts of the Theory have been proven to a very high degree, since they have served to corroborate a number of important predictions, such as that of the solar eclipse, which proposes that the sun deflects the light coming from the stars. when it approaches it as it heads toward Earth.