Question

What is simple equation ?

Answer 1

A simple equation is an expression containing at least one variable (=unknown value) and an "equals sign" ( = ) with a mathematical expression on each side of it. The equals sign says that both sides are exactly the same value.
An equation can be as simpleas x=0, or as hard as $4\left(3y^{99}\right)+76,42÷3x$ or harder.