Equations

Equation is construct in form of: $f(x) = C$ , where $x$ is some unknown variable ↗, $f$ is function ↗ of this variable and $C$ is some constant ↗ value. Solving an equation means finding inverse function $F$ such as $F(f(x)) = F(C)$ and $F(f(x)) = x$ which is the same as $x = F(C)$, where $F(C)$ is also a constant. For example:

We need to find such a function $F$ that will be applied to constant to give us value of $x$. We can apply inverse operation for number $-4$ is on the left side together with $x$ to leave $x$ alone with its power:

Then we can inverse power of $x$ applying $\sqrt{}$ to both sides:

And now we can unwrap $x$ to get both solutions to the equation: $x_1 = -7$ and $x_2 = 7$. Solution inverse function $F$ looks like this: