In Graphic Geometry, Technical Drawing - Mechanical Engineering Drawing, the establishment of the measured axis projection of an object has several methods. Some methods are made from two basic rectangular planes: equilibrium, equilibrium, oblique... The method of backprojection from the system of two perpendicular projection planes is a method of inverted space thinking, which builds a more effective inverted three-dimensional view of the object. Helping learners, readers and practitioners have more methods of checking and collating 3D objects, helping to perform the job better and more accurately to be applied in teaching the subject of Drawing - Technical Drawing.In Graphic Geometry, Technical Drawing - Mechanical Engineering Drawing, the establishment of the measured axis projection of an object has several methods. Some methods are made from two basic rectangular planes: equilibrium, equilibrium, oblique... The method of backprojection from the system of two perpendicular projection planes is a method of inverted space thinking, which builds a more effective inverted three-dimensional view of the object. Helping learners, readers and practitioners have more methods of checking and collating 3D objects, helping to perform the job better and more accurately to be applied in teaching the subject of Drawing - Technical Drawing.