Equations are expressions, so you need to use the "colon-equal" (:=) to define equations involving one or more variables in Maple.
For example: consider the following equation in one variable: 12x - 5=0 , we want to solve for x.
To enter and store this equation for subsequent processing, use the following commands in Maple:
>Eqn : = 12*x-5 (Eqn is a name that I gave to this equation, you can name it anything you want!)
To solve this equation, use the solve (for exact arithmetic) or fsolve (for floating point arithmetic) command as follows:
> Ans : = solve(Eqn=0,x); (The solution will be stored in the variable "Ans")
To learn more about solving equations, download the attached Maple file below and follow along!