1. The problem statement, all variables and given/known data Let ABC be an equilateral triangle with side 10 cm and let P be a point inside the triangle at a distance of 2 cm from the side AB. Given --> AB = BC = CA = 10cm and PD = 2 cm. If PD, PE, PF are the perpendiculars to the three sides, find out the sum, PD + PE + PF. Here is the image : http://postimage.org/image/1lt6hjgw4/ [Broken] 2. Relevant equations I am not sure which equation is most relevant being a geometry question. 3. The attempt at a solution I tried using similarity of triangles and Pythagoras theorem and trigonometry. I tried messing up all these things but failed to get the solution.