Section 3.9 3. (12 pts) A 13-foot ladder is leaning against a vertical wall (see figure) when Jack begins pulling the foot of the ladder away from the wall at a rate of 0.5 ft/s. How fast is the top of the ladder sliding down?Strategy for Solving Related Rate Problems 1. Understand the Problem drow a snapshot - draw a picture or two L picture - read the problem several times 2. Tidentify - known , given by the problem - unknown, what you want to find5. Solve/Interpret solve for the unknown rate interpret the answer by' writing a complete sentence with appropriate units Formulae Object Volume Surface Area Sphere SA = 4ATT- Conc W - arg | wy, where a -length of side Colinde Rectangular Prism