I really can't figure out what this problem is telling me to do. I've tried for the last 20 minutes but I just don't know how to make the function and I don't know where to start. Please help!
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A box with an open top is to be constructed from a rectangular piece of cardboard with dimensions W inches by L inches by cutting out equal squares of side x at each corner and then folding up the sides. (W = 14 in. and L = 25 in).
(a) Find a function that models the volume V of the box.
(b) Find the values of x for which the volume is greater than 240 in3. (Give each answer correct to three decimal places.)
(c) Find the largest volume that such a box can have. (Round your answer to three decimal places.)
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Thank you in advance for your help!