Plane provides interface for solving plane geometrical problems using the method of coordinates. If a construction can be produced with ruler and compass through finite number of steps, a user can make the construction using the graphical interface of Plane. Every time user creates a new construction (e.g. draws a line), its parameters are calculated symbolically. In the end user can write an equation with these parameters, which would reflect the geometric property of the construction that is required to prove. Because the syntax of symbolic expressions Plane operates with, complies with the syntax of Mathematica by Wolfram the user can use the powerful functions of the software package to simplify the equation and, thus, solve the problem.