1. The problem statement, all variables and given/known data An object is placed at 30 cm in front of a diverging lens with a focal length of 10 cm. What is the image distance? 2. Relevant equations 1/f = 1/do + 1/di 3. The attempt at a solution I thought this was a straight-forward question: 1/di = 1/-f - 1/do 1/di = (1/-10 cm) - (1/30 cm) 1/di = -0.066 cm di = 1/-0.066 cm = -15 cm BUT- the answer provided to me states that the answer is -7.5cm. So what is it that I'm missing here?