Answer:
Answering the part about who created the first equation:
There are a lot of different ways to solving cubic equations, but the first one is given by Gerolamo Cardano, who published it, and the equation was created by Scipione del Ferro, an Italian mathematician who was born in 1465. He did not make a lot of other contributions to mathematics, some of his other works were related to the rationalization of fractions with denominators containing sums of cube roots
This equation was called "Cardano's formula", and originally only worked for depressed cubic equations ( x^3 + p*x + q = 0)
But there are variations that can be used for more general cubic equations, of the form:
a*x^3 + b*x^2 + c*x + d = 0.
