The document provides an overview of constrained optimization using Lagrange multipliers. It begins with motivational examples of constrained optimization problems and then introduces the method of Lagrange multipliers, which involves setting up equations involving the functions to optimize and constrain and a Lagrange multiplier. Examples are worked through to demonstrate solving these systems of equations to find critical points. Caution is advised about dividing equations where one side could be zero. A contour plot example visually depicts the constrained critical points.