Question

what is the ideal gas equation

Answer 1

a hypothetical gas whose molecules occupy negligible space and have no interactions, and which consequently obeys the gas laws exactly.

Answer 2

The relations known as Boyle's law, Charles' law, and Avogadro's law can be combined into an exceedingly useful formula called the Ideal Gas Equation.
The ideal gas law, also called the general gas equation, is the equation of state of a hypothetical ideal gas.